JP2012045996A - Power generation control device of hybrid vehicle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To achieve traction control of high response within an allowable range of charging and discharging to a battery, while preventing overcharge to a battery, upon traction control intervention.SOLUTION: A power generation control device of a hybrid vehicle includes an engine 3, a generator 5, a battery 8, a driving motor 11, a traction controller (Fig. 4), and a traction control corresponding power generation controller (Fig. 2). The traction controller performs, when wheel slip occurs to slip driving wheels 13 and 13, traction control to decrease a torque command value to the driving motor 11. A traction control corresponding power generation controller has a function to reduce the generated power, when the charging and discharging amount to the battery 8 exceeds the predefined charging and discharging allowable range by intervention of the traction control (Fig. 7).

Description

  The present invention relates to a power generation control device for a hybrid vehicle that includes a generator driven by an engine and performs traction control that suppresses wheel slip.

  Conventionally, in a vehicle controller, the wheel acceleration is calculated based on the rotation speed of the traveling motor, and the wheel slip is calculated from the calculated wheel acceleration and the vehicle body acceleration calculated based on the torque command value of the traveling motor. Determine presence or absence. When it is determined that there is wheel slip, the torque command value to the traveling motor is decreased and commanded to the motor controller (hereinafter referred to as “traction control”). When it is determined that there is no wheel slip, control is performed so that the torque command value for the travel motor becomes a command value for normal travel according to the accelerator pedal depression amount. As a result, there is known a drive control device for an electric vehicle that aims to enable smooth running on a road surface with low frictional resistance (see, for example, Patent Document 1).

JP-A-8-182118

  However, when the drive control according to the prior art is performed when the chargeable / dischargeable power is limited, if it is determined that there is wheel slip, control is performed so as to reduce the drive power. A large power difference occurs in the power. However, the allowable value of the chargeable / dischargeable battery power is small due to the limitation of the chargeable / dischargeable power, and the driving force cannot be reduced to the target value required for the traction control. Therefore, there is a problem that the desired traction cannot be obtained and desired acceleration cannot be obtained.

  In addition, if the battery is charged beyond the chargeable / dischargeable power, the desired traction can be obtained, but an excessive increase in internal resistance due to excessive charging can cause an extreme voltage increase and impair the durability of the battery. There was a problem of having sex.

  The present invention has been made paying attention to the above problem, and at the time of traction control intervention, while preventing overcharging of the battery, it is possible to realize traction control with high response within an allowable range of charge / discharge amount to the battery. An object of the present invention is to provide a power generation control device for a hybrid vehicle.

In order to achieve the above object, a power generation control device for a hybrid vehicle of the present invention is a means comprising an engine, a generator, a battery, a drive motor, traction control means, and traction control-compatible power generation control means. .
The generator is driven by the engine and generates electric power for driving the vehicle.
The battery stores the electric power generated by the generator by charging.
The drive motor drives drive wheels with drive power generated by discharging the battery.
The traction control means performs traction control to reduce a torque command value to the drive motor when a wheel slip occurs in which the drive wheel slips.
The power generation control means corresponding to the traction control has a function of reducing the generated power when the charge / discharge amount to the battery exceeds a predetermined charge / discharge amount allowable range due to the intervention of the traction control.

Therefore, when the charge / discharge amount to the battery exceeds a predetermined charge / discharge amount allowable range due to the intervention of traction control, the traction control-compatible power generation control means performs control to reduce the generated power.
In other words, if traction control intervenes during power generation travel, the drive power will decrease, but at this time it will be generated between the drive power and the generated power by performing a control to reduce the generated power by exceeding the charge / discharge amount allowable range. The power difference to be performed is kept small, and the charge / discharge amount of the battery falls within a predetermined charge / discharge amount allowable range.
For this reason, at the time of traction control intervention, when the chargeable / dischargeable power to the battery is limited, overcharge exceeding the allowable charge amount range of the battery is prevented. In addition, when the traction control intervention is performed, even if the chargeable / dischargeable power to the battery is limited, a reduction in the driving force is allowed, so that the traction control is realized with a high response within the allowable charge / discharge amount range of the battery. Is done.
As a result, at the time of traction control intervention, traction control can be realized with high response within the allowable range of charge / discharge amount to the battery while preventing overcharging of the battery.

1 is a system configuration diagram showing an overall system of a series hybrid vehicle (an example of a hybrid vehicle) to which a power generation control device of Embodiment 1 is applied. It is a flowchart which shows the flow of the electric power generation control operation performed with the system controller in the electric power generation control apparatus of Example 1. FIG. It is a torque map figure which shows the relationship table of the accelerator opening degree, rotation speed, and torque which are used by the target torque calculation process among the electric power generation control operations of FIG. It is a block diagram which shows the process of the traction control part among the electric power generation control operations of FIG. It is a block diagram which shows a drive torque calculation process among the electric power generation control operations of FIG. FIG. 3 is a chargeable / dischargeable power map showing chargeable / dischargeable power with respect to battery temperature used in the drive torque calculation process in the power generation control operation of FIG. 2. FIG. 3 is a control block diagram illustrating target generated power calculation processing in the power generation control operation of FIG. 2. FIG. 3 is an operating point map diagram showing a relationship table between a rotational speed and torque used in power generation control in the power generation control operation of FIG. It is a traction control corresponding | compatible map figure which shows the relationship table of the reduction | decrease electric power at the time of a slip, and addition rotation speed. It is a flowchart which shows the process of the traction control part among the electric power generation control operations of FIG. It is a control block diagram which shows a wheel speed servo system. It is a flowchart which shows a drive torque calculation process among the electric power generation control operations of FIG. It is a block diagram which shows the calculation process of the target torque and target rotation speed among the electric power generation control operations of FIG. It is a flowchart which shows the calculation process of the target torque and target rotation speed among the electric power generation control operations of FIG. Time indicating characteristics of accelerator opening, actual motor speed, CAN vehicle speed, drive power, generated power, charge / discharge power, generator speed, and generator torque when chargeable / dischargeable power is limited in the comparative example It is a chart. In the first embodiment, the characteristics of accelerator opening, actual motor speed, CAN vehicle speed, drive power, generated power, charge / discharge power, generator speed, and generator torque when chargeable / dischargeable power is limited are shown. It is a time chart.

  Hereinafter, the best mode for realizing a power generation control device for a hybrid vehicle of the present invention will be described based on Example 1 shown in the drawings.

First, the configuration will be described.
FIG. 1 is a system configuration diagram illustrating an entire system of a series hybrid vehicle (an example of a hybrid vehicle) to which the power generation control device of the first embodiment is applied. The overall configuration will be described below with reference to FIG.

  As shown in FIG. 1, the series hybrid vehicle of the first embodiment includes a system controller 1, an engine controller 2, an engine 3, a generator controller 4, a generator 5, a generator inverter 6, and a battery controller 7. A battery 8, a drive motor controller 9, a drive inverter 10, a drive motor 11, a speed reducer 12, and drive wheels 13 and 13. 14 is a wheel speed sensor, 15 is a motor rotation sensor, and 16 is a current sensor.

  The series hybrid vehicle is a series type (series type) hybrid vehicle in which the engine 3 is used only for power generation and the drive motor 11 is used only for driving and regeneration of the drive wheels 13 and 13. Simply put, it is an electric vehicle equipped with a power generation system. Therefore, there is no travel mode using the engine 3 as the travel mode, and only the electric vehicle travel mode (= EV travel mode).

  The engine 3 transmits a driving force for power generation to the generator 5. The generator 5 is rotated by the driving force of the engine 3 to generate power. That is, the power generator is mainly composed of the engine 3 and the generator 5. Further, the generator 5 also has a function as a motor, and can consume electric power by cranking at the time of starting the engine or by rotating the engine 3 by using the driving force of the generator 5. it can.

  The generator inverter 6 is connected to the generator 5, the battery 8, and the drive inverter 10, and converts AC power generated by the generator 5 into DC or reverse conversion.

  The battery 8 charges the regenerative power of the generator 5 and the drive motor 11 and discharges the drive power.

  The drive inverter 10 converts the DC power supplied from the battery 8 and the generator inverter 6 into an AC current of the drive motor 11 or performs reverse conversion.

  The drive motor 11 generates a driving force and transmits the driving force to the driving wheels 13 and 13 through the speed reducer 12. Then, when the vehicle is traveling, when it is rotated by the drive wheels 13 and 13, energy is regenerated by generating a regenerative driving force.

  In order to realize the engine torque command value commanded from the system controller 1, the engine controller 2 responds to a signal such as the engine speed or the temperature of the engine 3 to determine the throttle opening, ignition timing, fuel injection amount of the engine 3. Adjust.

  The generator controller 4 performs switching control of the generator inverter 6 in accordance with the state of the generator such as the rotational speed and voltage in order to realize the generator torque command value commanded from the system controller 1.

  The battery controller 7 measures the battery SOC (referred to as a battery charge state, SOC is an abbreviation of “State Of Charge”) based on the current and voltage charged / discharged to the battery 8, and outputs it to the system controller 1. Also, the temperature of the battery 8, the charging efficiency of the battery 8, the input power according to the battery SOC, and the output power according to the battery SOC are calculated and output to the system controller 1.

  The drive controller 9 performs switching control of the drive inverter 10 according to the state of the drive motor 11 such as the rotational speed and voltage in order to realize the drive torque commanded from the system controller 1.

  The system controller 1 responds to the driver's accelerator pedal operation amount, vehicle speed, (road surface) gradient and other vehicle conditions, battery SOC from the battery controller 7, input power, output power, power generated by the generator 5, and the like. The drive torque is commanded to the drive motor 11. Furthermore, the target generated power PG for charging the battery 8 and supplying it to the drive motor 11 is calculated.

  Next, the operation of the system controller 1 will be described based on the control flowchart shown in FIG. 2 (traction control-compatible power generation control means). This operation corresponds to the drive request when the battery temperature is low and charging / discharging to the battery 8 is restricted (battery input possible power (PIN) = low, battery output possible power (POUT) = low). Taking a case where slip occurs and direct traction control is performed during direct distribution in which generated power is generated and driving power is consumed according to the generated power. These calculations are executed in the system controller 1 every control calculation cycle (for example, 10 msec).

In the input process of step S1, signals necessary for the control calculation described below are acquired by sensor input or communication from another controller.
The generator rotational speed ωg of the generator 5 is acquired by a motor rotation sensor such as a resolver or an encoder. Similarly, the drive motor rotational speed ωm of the drive motor 4 is acquired by a motor rotation sensor 15 such as a resolver or an encoder. The accelerator opening degree θ by the driver operation is acquired by an accelerator opening sensor. The voltage of the battery 8 is obtained from the power supply voltage value transmitted from the voltage sensor provided in the DC power supply line or the battery controller 7 as the DC voltage value Vdc [V]. The actual generated power Pg is obtained from the DC voltage value Vdc [V], the battery current sensor value [A], and the drive current sensor value [A] of the battery 8 and the power actually generated by the generator 5.

  In the target torque calculation process of step S2, the target torque command value Tm is set from the accelerator opening-torque table shown in FIG. 3 based on the accelerator opening θ and the vehicle speed V.

  In the traction control in step S3, as shown in FIG. 4, the slip state of the drive wheels 13 and 13 is judged based on the motor rotational speed ωm and the driven wheel speed ωv, and the slip torque command value Tslip for eliminating the slip is calculated. To do. Regarding the torque control process, if it is determined that there is slip, the calculated slip torque command value is set to Tslip, and if it is determined that there is no slip, control is performed so that the torque command value set in step S2 is set to Tm. To do. Details of the processing of the traction control unit will be described later.

  In the drive torque calculation process of step S4, based on the slip torque command value Tslip, the LB input possible power Pin, the LB output possible power Pout, the drive control generated power Pg, and the drive motor rotational speed ωm, from the block diagram shown in FIG. Set the drive torque TD. The chargeable / dischargeable power is a value calculated by the battery controller 7, and uses a chargeable / dischargeable power map for the battery temperature as shown in FIG. In the drive torque calculation flow, the lower limit drive torque Tmin is calculated from the map based on the value obtained by adding the drive control generated power Pg consumed by the drive, the power Pin that can be charged to the battery, and the drive motor rotational speed ωm. Similarly, the upper limit drive torque Tmax is calculated from the map based on the value obtained by adding the drive control generated power Pg, the power Pout that can be output from the battery, and the drive motor rotational speed ωm.

  In the target generated power calculation process in step S5, based on the slip torque command value Tslip, the drive torque TD, the drive motor rotational speed ωm, and the target generated power PGa before slip intervention, the block 8 shown in FIG. A reduced power Pdown that is not allowed to be charged / discharged and a target generated power PG are set. Details of the target generated power calculation process will be described later.

  In the power generation control in step S6, the engine 3 and the generator 5 are controlled in order to realize the target generated power PG. At the time of non-traction control, the relationship between the rotational speed of the generator 5 and the torque of the engine 1 preset in order to obtain generated power in consideration of fuel consumption and responsiveness, and an operating point map (shown by a solid line in FIG. 8) The generator rotational speed target value and the engine torque target value are obtained using α rays), the engine torque target value is output to the engine controller 2, and the generator rotational speed target value is output to the generator controller 4.

  During the traction control, the target torque TG and the target rotational speed ωG are set based on the target generated power PG, the reduced power Pdown during the slip, and the rotational speed ωGa before the slip. This is because the addition rotational speed ωGb to be added at the time of traction control is calculated from the map of the reduced power Pdown and the additional rotational speed ωGb shown in FIG. 9, and is added to the rotational speed ωGa before the slip, thereby adding the target rotational speed. Set ωG. Here, the reason why the additional rotational speed ωGb is increased as the reduced power Pdown at the time of slip is larger is that the higher the reduced power Pdown at the time of slip, the higher the engine speed that is increased at the moment the torque is removed. This is because the target rotational speed is set.

  In the power generation control, the generated power PG to be actually generated is calculated in consideration of the losses of the generator inverter 6 and the generator 5 and output to the generator inverter 6. Then, the engine speed target value ωG, which is the engine speed target value, is output to the engine controller 2, and the target torque TG, which is the torque target value of the generator 5, is output to the generator controller 4. The machine 5 and the generator inverter 6 can generate power with a desired power generation amount.

Next, processing in the drive motor controller 9, the generator controller 4, and the engine controller 2 will be described.
First, in the current command value calculation process of the drive motor controller 9, the dq-axis current target values id ^* and iq ^* are obtained from the table based on the drive torque command value TD calculated in step S5, the drive motor rotational speed ωm, and the DC voltage value Vdc. Seek and ask. In the current control, first, the dq axis current values id and iq are calculated from the three-phase current values iu, iv and iw and the drive motor rotational speed ωm. The dq-axis voltage command values vd and vq are calculated from the deviation between the dq-axis current target values id ^* and iq ^* and the dq-axis current id and iq calculated in the current command value calculation process. Note that non-interference control may be added to this portion. Next, the three-phase voltage command values vu, vv, vw are calculated from the dq-axis voltage command values vd, vq and the drive motor rotational speed ωm. PWM signals (on duty) tu [%], tv [%], tw [%] are calculated from the three-phase voltage command values vu, vv, vw and the DC voltage Vdc. By controlling the switching element of the inverter 10 to open / close with the PWM signal thus obtained, the drive motor 11 can be driven with a desired torque indicated by the torque command value. Similarly, the generator controller 4 receives the target generated power PG from the system controller 1 and performs the same current command value calculation processing and current control calculation as the drive motor controller 9. The engine controller 2 adjusts the throttle, ignition timing, and fuel injection amount of the engine 3 in accordance with signals such as the rotational speed and temperature of the engine 3 in order to realize the engine torque command value commanded from the system controller 1. .

Next, traction control will be described based on the flowchart shown in FIG.
The traction control performs wheel speed servo so that the driving wheel speed calculated from the motor rotation speed ωm follows the target vehicle speed at the time of wheel slip. The wheel speed servo calculates the slip torque command value Tslip using the robust model matching control shown in FIG. If this slip torque command value Tslip exceeds the predetermined allowable range for battery charge / discharge power, it has a function to adjust the generated power, and the time constant of the model matching compensator is set depending on whether or not to adjust. It is characterized by changing. The target driving wheel speed ωt is a value obtained by adding a constant value (for example, 5 km / h) to the driven wheel speed ωv.

  In step S3-1, the slip state is determined from the drive motor rotational speed ωm and the driven wheel speed ωv.

  In step S3-2, it is determined whether or not the generator 5 is used (exceeds a predetermined allowable range for battery charge / discharge power). If the generator 5 is used, the process proceeds to step S3-3, and if not, the process proceeds to step S3-4.

  In step S3-3, the gain of the model matching compensator used in the wheel speed servo is set to a LOW value (low gain value), and the process proceeds to step 3-5.

  In step S3-4, the gain of the model matching compensator used in the wheel speed servo is set to the HI value (high gain value), and the process proceeds to step 3-5.

  In step S3-5, a wheel speed servo calculation is performed to obtain a drive wheel torque command value Tslip necessary for the drive wheel speed ωm to coincide with the target drive wheel speed ωt. The time constant of the model matching compensator in the wheel speed servo uses the value set in step S3-3 and step S3-4.

Next, details of the drive torque calculation processing unit will be described based on the flowchart of the drive torque calculation processing unit shown in FIG.
In the drive torque calculation process, the drive torque TD is set based on the slip torque command value Tslip, the LB input possible power Pin, the LB output possible power Pout, the drive control generated power Pg, and the drive motor rotational speed ωm. The lower limit drive torque Tmin is calculated from the map based on the value obtained by adding the drive control generated power Pg consumed by the drive, the power Pin that can be charged to the battery 8, and the drive motor rotational speed ωm. Similarly, the upper limit drive torque Tmax is calculated from the map from the value obtained by adding the drive control generated power Pg and the power Pout that can be output from the battery 8 and the drive motor rotational speed ωm.
These calculations are executed in the system controller 1 every control calculation cycle (for example, 10 msec).

  In step S4-1, the LB input possible power Pin is subtracted from the drive control generated power Pg and stored in the power generation possible lower limit power Pmin.

  In step S4-2, the drive requestable lower limit torque Tmin is calculated from the minimum drive torque map from the power generation possible lower limit power Pmin and the drive motor rotational speed ωm.

  In step S4-3, the LB input possible power Pout is subtracted from the drive control generated power Pg and stored in the power generation possible upper limit power Pout.

  In step S4-4, the drive requestable upper limit torque Tmax is calculated from the maximum drive torque map from the power generation allowable upper limit power Pmax and the drive motor rotational speed ωm.

  In step S4-5, with respect to the slip torque command value Tslip, the lower limit value of the value is limited by Tmin, and the upper limit value of the value is limited by Tmax to obtain the drive torque TD. Then go to END.

Next, the details of the target generated power calculation process will be described based on the target generated power calculation process block diagram shown in FIG.
In the target generated power calculation process, the target generated power PG and the reduced power Pdown are calculated.
The calculation formula is performed using a calculation formula that takes into consideration the generated power Pga immediately before slip intervention, the slip torque command value Tslip, the drive motor rotational speed ωm, and the drive torque TD. The formula is
PDt ＝ Tslip ・ ωm
PD = TD ・ ωm
Pdown = PD−PDt
Pdown = TD ・ ωm−Tslip ・ ωm
Pdown = (TD−Tslip) ωm
PG = PGa-Pdown
PG = PGa− (TD−Tslip) ωm (1)
It is.
here,
Tslip: Slip torque command value ωm: Drive motor speed
PDt: Slip drive command power
TD: Drive torque command value
PD: Actual drive command power
PGa: Power generation just before slip intervention
Pdown: Decreasing power
PG: Target generated power.

Next, the details of the power generation control will be described based on the block diagram of the power generation control shown in FIG. An additional rotational speed ωGb, a target torque TG, and a target rotational speed ωG are determined based on the target generated power PG, the rotational speed ωGa immediately before the slip intervention, and the reduced power Pdown at the time of slipping. The formula is
ωG = ωGa + ωGb
TG = PG / ωG
TG = {PGa− (TD−Tslip) ωm} / (ωGa + ωGb) (2)
It is.
here,
ωG: target rotational speed ωGa: rotational speed before slip intervention ωGb: additional rotational speed
TG: Target torque.

  The engine 3 and the generator 5 are controlled in order to realize the target generated power PG. During non-slip in normal driving, the operating point map shown in the solid line in FIG. 8 is a relationship between the rotational speed of the generator 5 and the torque of the engine 3 set in advance to obtain the generated power in consideration of fuel consumption and responsiveness. , The generator rotational speed target value and the engine torque target value are obtained, the engine torque target value is output to the engine controller 2, and the generator rotational speed target value is output to the rotational speed control. However, during traction control, the operating point map (α line) is removed, and the target torque TG and the target rotational speed ωG are set based on the target generated power PG, the reduced power Pdown during the slip, and the rotational speed ωGa before the slip. . This is based on the map of the reduced power Pdown at the time of slip and the additional rotational speed ωGb, and calculates the rotational speed to be added at the time of traction control and adds the rotational speed ωGa before the slip to set the target rotational speed ωG. A value obtained by dividing the target rotational speed ωg from the target generated power PG is the target torque. Increasing the additional rotation speed as the power reduction at the time of slip increases, and the increase in the engine speed increases at the moment the torque due to friction increases as the slip reduction power increases, the target speed in anticipation of this in advance It is to make it.

  Next, a process for calculating the target rotational speed ωG and the target torque TG will be described based on the flowchart shown in FIG.

  In step S6-1, using the addition rotation speed map (FIG. 9), the addition rotation speed ωGb is calculated from the reduced power value Pdown at the time of slip intervention.

  In step S6-2, the rotational speed immediately before the slip intervention is stored in ωGa.

  In step S6-3, the additional rotational speed ωGb calculated in step S6-1 and the rotational speed ωGa immediately before slip intervention stored in step S6-2 are added to calculate the target rotational speed ωG that is the engine rotational speed target value. To do. This target rotational speed ωG is output to the engine controller 2.

  In step S6-4, the target torque PG, which is the torque target value of the generator 5, is calculated by dividing the target generated power PG by the target rotational speed ωG, and the process proceeds to END. This target torque TG is output to the generator controller 4.

Next, the operation will be described.
First, “About problems in power generation control of a comparative example” will be described. Next, the operation of the power generation control device for the hybrid vehicle according to the first embodiment will be described by dividing it into “power generation control operation corresponding to traction control” and “effect confirmation operation by power generation control corresponding to traction control”.

[Problems in power generation control of comparative example]
In the comparative example, the power generation control and the traction control are performed independently of each other, and when it is determined that there is wheel slip in the traction control, the motor torque command value is set to smoothly travel on a road surface with low frictional resistance. It is assumed that control to decrease is performed.

By the way, in a so-called series hybrid vehicle, when chargeable / dischargeable power, which is input / output power of a battery, is limited due to a temperature drop or the like, direct distribution is aimed at preventing charging / discharging of the battery. There is a need to implement control.
Here, the direct power distribution control is control in which electric power is generated in a generator according to a required value of driving force, and actual generated power generated by the generator is consumed with driving power without excess or deficiency. In other words, direct power distribution control calculates the drive power necessary to achieve the desired drive torque calculated from the accelerator opening, vehicle speed, etc., and generates the required drive power as a generated power command value without excess or deficiency. It will be realized by controlling.

  However, when the traction control of the comparative example is performed when the internal resistance of the battery is high due to a temperature drop or the like and the chargeable / dischargeable power is limited, the drive power is reduced if it is determined that there is wheel slip. Therefore, a large power difference occurs between the generated power and the driving power. However, the allowable value of the battery chargeable / dischargeable power is small due to the limitation, and the driving force cannot be reduced to the target value required for the traction control. For this reason, the desired traction cannot be obtained, and the desired acceleration cannot be obtained.

  In addition, if the battery is charged beyond the chargeable / dischargeable power, the desired traction can be obtained, but an excessive increase in internal resistance due to excessive charging will cause an extreme voltage increase, impairing the durability of the battery. There is also a possibility of end.

FIG. 15 shows a time chart showing the problems of the comparative example.
FIG. 15 shows the state of power generation control and drive control when the chargeable / dischargeable power is limited. The vehicle travels with direct power distribution during normal travel, and generates power with constant power during traction control when slip occurs. It shows how it is going. First, at time T1, slip occurs during acceleration, and the actual motor rotational speed ωm rapidly increases. At time T2, it is determined that there is slip based on the acceleration of the motor rotation, the slip ratio, and the like. At this time, traction control is started, but it can be seen that the charging power exceeds the limit value (Pin) and charging is performed. At time T3, when traction is recovered, it can be seen that the dischargeable power exceeds the limit value (Pout) and is discharged.

[Power generation control function for traction control]
At the time of power generation running in which chargeable / dischargeable power is limited, the flow of step S1, step S2, step S3, step S4, step S5, and step S6 is repeated every predetermined control period in the flowchart of FIG. By this control processing operation, even if traction control intervenes, power generation control corresponding to this control intervention is performed.
That is, in step S1, an input process for acquiring information necessary for the control calculation is performed. In step S2, a target torque command value Tm is set based on the accelerator opening θ and the vehicle speed V. In the traction control in step S3, the slip state of the drive wheels 13, 13 is determined. If it is determined that there is slip, the slip torque command value is Tslip. If it is determined that there is no slip, the torque command value is Tm. Thus, the drive torque is controlled. In the drive torque calculation process of step S4, based on the slip torque command value Tslip, the LB input possible power Pin, the LB output possible power Pout, the drive control generated power Pg, and the drive motor rotational speed ωm, from the block diagram shown in FIG. The driving torque TD is set. In the target generated power calculation process in step S5, based on the slip torque command value Tslip, the drive torque TD, the drive motor rotational speed ωm, and the target generated power PGa before slip intervention, the block 8 shown in FIG. A reduced power Pdown that is not allowed to be charged / discharged and a target generated power PG are set. In the power generation control in step S6, the engine 3 and the generator 5 are controlled in order to realize the target generated power PG.

The first embodiment has a function of reducing the generated power when the driving power is reduced and the battery charge / discharge power exceeds a predetermined allowable range by traction control during wheel slip. Specifically, as shown in FIG. 7 and Equation (1), the reduced power Pdown that does not allow charging / discharging of the battery 8 is calculated from the difference between the shaft drive command power PD and the slip drive command power PDt. Then, the target generated power PG is calculated from the difference between the target generated power PGa before the slip intervention and the reduced power Pdown.
In other words, if traction control intervenes during power generation travel, the drive power (slip drive command power PDt) decreases, but at this time by performing control to reduce the generated power for exceeding the charge / discharge amount allowable range, The power difference generated between the generated power and the generated power is suppressed to be small, and the charge / discharge amount of the battery 8 is within a predetermined charge / discharge amount allowable range.
For this reason, at the time of traction control intervention and when chargeable / dischargeable power to the battery 8 is limited, overcharge exceeding the charge amount allowable range of the battery 8 is prevented. In addition, when the traction control intervention is performed, even when the chargeable / dischargeable power to the battery 8 is limited, the reduction of the driving force is allowed, so that the traction control has a high response within the allowable charge / discharge amount range for the battery 8. To be realized. In other words, at the time of normal temperature where the restriction on the chargeable / dischargeable power to the battery 8 is moderate, targeted traction control is realized with high response by reducing the driving force up to the target value. In the case of a low temperature where the limit of chargeable / dischargeable power to the battery 8 is severe, the traction control is realized with high response by reducing the driving force up to the charge / discharge allowable range limit.

In the first embodiment, in order to realize the target generated power PG obtained by subtracting the reduced power Pdown from the target generated power PGa before the slip intervention, at least the generator rotational speed is maintained at the rotational speed before the occurrence of the slip and the generator torque is reduced. Therefore, the generated power is lowered. In other words, during traction control, the engine 3's fuel efficiency optimum line (operation line = α line connecting the operating points of torque and rotation speed with the highest fuel efficiency to obtain the desired output for each output) is removed. Use points (Figure 8).
In this way, by setting the operating point from which the α-line with good fuel efficiency is removed, the generator torque is reduced without lowering the generator rotational speed, and the response generated by the engine rotational speed fluctuation generated to reduce the generated power. Delay can be reduced.
Because, in order to move the operating point on the α-ray and reduce the generator speed, it is necessary to first slightly increase the torque to cancel the inertia torque of the engine 3, and in order to stabilize the target generated power PG take time. However, this problem can be avoided by reducing the torque without reducing the engine speed, and the target generated power PG can be settled with high response. Similarly, when the generated power once reduced is increased again in the traction control, similarly, if the engine speed is once reduced, there is a response delay in returning to the target engine speed.

In the first embodiment, at the time of traction control intervention, the target rotational speed ωG in power generation control is set to a higher rotational speed than the generator rotational speed ωGa immediately before slip intervention. That is, as shown in FIG. 9, the addition rotational speed ωGb is determined by a value proportional to the reduced power Pdown at the time of slip, and as shown in FIG. 13, the target rotational speed ωG is set to the generator rotational speed ωGa immediately before slip intervention. The addition rotational speed ωGb is added to obtain.
Because when the traction control increases the number of revolutions of the generator 5, when the generated power once reduced is increased again, the amount of generated power is the product of the number of revolutions of the generator 5 and the torque, so the number of revolutions is high. Holding in the state can increase more generated power with less torque. As a result, it is possible to control the amount of power generation with high response when the rotation of the generator 5 is kept at a high speed rather than at a low speed. Further, when the traction control state is entered, the rotational speed of the generator 5 is increased, so that the driver can be alerted to the wheel slip.

In the first embodiment, in the power generation control at the time of traction control intervention, the engine 3 performs the rotational speed control and the generator 5 performs the torque control. That is, as shown in FIG. 13, the target engine speed ωG that is the engine speed target value is output to the engine controller 2, and the target torque TG that is the torque target value of the generator 5 is output to the generator controller 4. .
This is because the torque control in the engine 3 generates a torque that is slow in response and uncertain compared to the torque control in the generator 5. For this reason, in order to accurately realize the generated power required for the traction control, the generated torque that can be controlled with higher response is used as the basic control amount. Thus, by performing torque control with the generator 5, it is possible to obtain accurate torque with higher response than when performing torque control with the engine 3. Further, by performing torque control so that the generator 5 becomes the target generated power PG, the torque can be reduced with high response, and accurate generated power can be obtained.

In the first embodiment, in the case of traction control, in the case of traction control using a generator that realizes the subtracted target generated power PG, and in the case of non-generator traction by charging / discharging only the battery 8 without requiring subtraction of the target generated power PG. The control gain of traction control is changed depending on the case of control. That is, as shown in FIG. 10, in the traction control using the generator 5, the gain of the model matching compensator is set to a LOW value, and in the traction control not using the generator 5, the gain of the model matching compensator is set to HI. Set to value.
This is because there is a difference in response delay between when the traction control is performed only by the battery 8 (high response) and when the traction control is performed in consideration of the response of the generator 5 (low response). Therefore, by changing the control gain of the traction control, the engine 3 is not hunted, and even if the engine 3 is used together, the desired traction control can be realized.

[Effect confirmation by traction control power generation control]
FIG. 16 shows a time chart showing the effects of the first embodiment.
FIG. 16 shows the state of power generation control and drive control when the chargeable / dischargeable power is limited, as in FIG. 15 of the comparative example. The vehicle travels with direct power distribution until time T1 when the traction control starts. It shows how it is going.
First, at time T1, slip occurs during acceleration, and the actual motor rotational speed ωm rapidly increases. At time T2, as described in step S3, it is determined that there is a slip from the acceleration calculated from the motor rotation speed and the slip ratio. At this time, as described in step S4 and step S5, the target generated power PG (generated power) is calculated by calculating the reduced power Pdown that cannot be compensated by the battery chargeable / dischargeable power and adding it to the generated power PGa immediately before the slip intervention. Is decided. Then, as described in step S6, the generator rotational speed is determined by adding the rotational speed ωGb using the map considering the friction of the engine 3 from the reduced power Pdown and adding the rotational speed ωGa immediately before the slip intervention. Increase to several ωG. The generator torque at that time uses a torque that realizes the target generated power PG as a command value. At time T3, it follows the target rotational speed ωG set at time T2 and is kept constant thereafter, but by generating power with a high response, generator power equivalent to drive power can be obtained. ing.
As a result, it is understood that the charging power is allowed within the limit value (Pin) between time T2 and time T3.

  As described above, even in a state where the chargeable / dischargeable power is limited, during traction control, the reduced power Pdown that is not allowed by the chargeable / dischargeable power is maintained at a good power balance by lowering the target generated power PG. In addition, the α-rays are removed, and the engine torque is greatly reduced without lowering the engine speed, thereby realizing the desired generated power with high response. Then, by increasing the engine speed according to the reduced power Pdown, the target generated power PG considering the friction of the engine 3 is obtained. In addition, by using a region where the engine speed is high, the generated power can be restored with high response.

Next, the effect will be described.
In the hybrid vehicle power generation control device of the first embodiment, the following effects can be obtained.

(1) Engine 3 and
A generator 5 driven by the engine 3 to generate electric power for driving the vehicle;
A battery 8 for storing the power generated by the generator 5 by charging;
A drive motor 11 that drives the drive wheels 13 and 13 by drive power generated by the discharge of the battery 8;
Traction control means (FIG. 4) for performing traction control for reducing a torque command value to the drive motor 11 when a wheel slip occurs in which the drive wheels 13 and 13 slip.
Traction control-compatible power generation control means (FIG. 2) having a function of reducing the generated power when the charge / discharge amount to the battery 8 exceeds a predetermined charge / discharge amount allowable range due to the intervention of the traction control;
Is provided.
For this reason, at the time of traction control intervention, the traction control can be realized with high response within the allowable charge / discharge amount range of the battery 8 while preventing the battery 8 from being overcharged.

(2) The traction control compatible power generation control means (FIG. 2) maintains the generator speed of the generator 5 after the traction control intervention at least at the generator speed before the traction control intervention, The generated power is reduced by reducing the generator torque (FIG. 8).
For this reason, in addition to the effect of (1), when the generated power is reduced, the response of lowering the generated torque is higher than the response of lowering the generator speed, thereby preventing a delay in the response of the generated power reduction. it can.

(3) The traction control compatible power generation control means (FIG. 2) sets the generator speed of the generator 5 after the traction control intervention to a higher speed than the generator speed before the traction control intervention ( 9 and 14).
For this reason, in addition to the effect of (2), it is possible to perform power generation amount control with high response, and when the traction control state is entered, the driver 5 is alerted to wheel slip due to the increase in the number of revolutions of the generator 5. Can be urged.

(4) The traction control-compatible power generation control means (FIG. 2) performs the rotational speed control by the engine 3 and the torque control by the generator 5 when reducing the generated power by the intervention of the traction control ( FIG. 13 and FIG. 14).
For this reason, in addition to the effect of (2) or (3), it is possible to obtain an accurate torque with a higher response than when the torque control is performed by the engine 3, and a torque that can be the target generated power PG by the generator 5. By performing the control, the torque can be reduced to a high response, and accurate generated power can be obtained.

(5) The traction control means (FIG. 4) executes traction control by reducing the generated power, and executes traction control by charging / discharging the battery 8 without reducing the generated power. Thus, the control gain of the traction control is changed (FIG. 10).
For this reason, in addition to the effects (1) to (4), the difference in response delay depending on whether the generator 5 is used or not is suppressed, the engine 3 is not hunted, and the engine 3 can be used together. The traction control as intended can be realized.

  As described above, the power generation control device for a hybrid vehicle according to the present invention has been described based on the first embodiment. However, the specific configuration is not limited to the first embodiment, and the claims relate to each claim. Design changes and additions are allowed without departing from the scope of the invention.

  In the first embodiment, in the power generation control, the engine speed target value ωG is output to the engine controller 2 and the torque target value TG of the generator 5 is output to the generator controller 4, that is, the engine speed control of the engine 3 is performed. The example by the torque control of the generator 5 was shown. However, the rotational speed command ωG is sent to the generator controller 4, the rotational speed control is performed by the generator 5, the torque command is sent to the engine controller 2, the torque control is performed by the engine 3, and desired power generation is performed. You may make it do.

  The first embodiment employs a vehicle speed servo system such as a vehicle automobile speed control device (ASCD), and shows an example in which model matching control is used for a drive wheel speed servo system. However, the same effect can be obtained even when the servo system is configured using PI control or the like. As described above, when PI control or the like is used in the drive wheel speed servo system, the PI gain or the like is changed instead of changing the control constant of the robust compensator in FIG.

  In Example 1, the example which applied the electric power generation control apparatus to the series hybrid vehicle was shown. However, a parallel hybrid vehicle in which an engine, a power generation motor generator, and a travel motor generator are connected to a power split device using a planetary gear, or an assist hybrid vehicle in which a power generation motor generator and a travel motor generator are connected to an engine. It can be applied to the above. In short, the present invention can be applied to any hybrid vehicle including a generator (power generation motor generator) driven by an engine and a drive motor (travel motor generator) for driving drive wheels.

1: System controller 2: Engine controller 3: Engine 4: Generator controller 5: Generator 6: Generator inverter 7: Battery controller 8: Battery 9: Drive motor controller 10: Drive inverter 11: Drive motor 12: Reducer 13 : Driving wheel 14: Wheel speed sensor 15: Motor rotation sensor 16: Current sensor

Claims (5)

Engine,
A generator driven by the engine to generate electric power for driving the vehicle;
A battery for storing the power generated by the generator by charging;
A drive motor for driving the drive wheels by drive power generated by discharging the battery;
Traction control means for performing traction control to reduce a torque command value to the drive motor when a wheel slip occurs in which the drive wheel slips;
Traction control-compatible power generation control means having a function of reducing the generated power when the charge / discharge amount to the battery exceeds a predetermined charge / discharge amount allowable range due to the intervention of the traction control;
A power generation control device for a hybrid vehicle, comprising: In the power generation control device for a hybrid vehicle according to claim 1,
The traction control compatible power generation control means maintains the generator rotational speed of the generator after the traction control intervention at least at the generator rotational speed before the traction control intervention, and reduces the generator torque. A power generation control device for a hybrid vehicle, wherein the power generation is reduced. In the hybrid vehicle power generation control device according to claim 2,
The power generation control means corresponding to the traction control sets the generator rotational speed of the generator after the traction control intervention to a higher rotational speed than the generator rotational speed before the traction control intervention. Control device. In the power generation control device for a hybrid vehicle according to claim 2 or claim 3,
The power generation control means for a hybrid vehicle, wherein the power generation control means corresponding to the traction control performs a rotational speed control by the engine and a torque control by the generator when the generated power is reduced by the intervention of the traction control. apparatus. In the power generation control device for a hybrid vehicle according to any one of claims 1 to 4,
The traction control means increases the control gain of traction control when performing traction control by reducing the generated power and when performing traction control by charging / discharging the battery without reducing the generated power. A power generation control device for a hybrid vehicle, characterized by being changed.