JP2007245769A - Driving controller for vehicle, automobile and driving control method for vehicle - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To suppress the revolving speed of an engine for power generation from being overshot even when decreasing the generated power of a power generation motor. <P>SOLUTION: A vehicle is provided with a power generation motor 27 connected to the output shaft of an engine 28 for power generation for generating a power by the engine 28 and a driving motor 26 for driving a wheel by using a power generated by the power generation motor 27. This vehicle is provided with a generated power decrease processing part 29 for detecting the decrease of the generated power of the power generation motor 27; an engine overshoot revolution speed calculating part 30 for predicting the generation of the overshoot of the revolution speed of the engine 28; and a surplus generated power calculation part 32 for suppressing the increase of the revolution speed of the engine when the decrease of the generated power is detected by the generated power decrease processing part 29, and it is predicted that the revolution speed of the engine 28 is overshot by the engine overshoot revolution speed calculation part 30. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a vehicle drive control device, an automobile, and a vehicle drive control method for causing a drive motor to drive wheels using electric power generated by driving a generator motor by an engine.

Conventionally, an engine rotational speed target value of a vehicle (hereinafter referred to as “series hybrid vehicle”) that drives a wheel by a drive motor using electric power generated by driving a power generation motor by an engine is, for example, a patent document As disclosed in FIG. 1, the predetermined rotational speed at which the power generation efficiency is highest, that is, the engine output is set to the rotational speed having the highest efficiency. Further, for example, a technique disclosed in Patent Document 2 is known as a means for preventing the motor from over-rotating.
JP-A-11-252709 JP-A-9-150638

  In the prior art, since there is a difference in the responsiveness between the power generation motor and the power generation engine, the required drive output in the drive motor is reduced, so that the generated power (power generation output) of the power generation motor and the output of the power generation engine are reduced. When a command to decrease is issued, the power generation output of the power generation motor is reduced to a high response, but the output response of the power generation engine is delayed with respect to the power generation motor. As a result, the rotational speed of the power generation engine may overshoot, and the rotational speed may exceed the limiter. As a result, an excessive load on the engine may occur, or the passenger may feel uncomfortable.

That is, in the conventional technology, due to the difference in response between the power generation motor and the power generation engine, there is a possibility that the rotational speed of the power generation engine may overshoot when the generated power in the power generation motor is reduced. .
In Patent Document 2, although over-rotation of the motor can be prevented, engine overshoot is not necessarily completely suppressed as in Patent Document 1.
An object of the present invention is to suppress overshooting of the rotational speed of a power generation engine when power generated by a power generation motor is reduced.

In order to solve the above problems, the present invention provides:
A generator motor connected to the output shaft of the engine and driven by the engine to generate electric power; and a drive motor for driving wheels using the electric power generated by the generator motor, the output of the drive motor being reduced In this case, the vehicle drive control apparatus is characterized in that at least one of the engine and the power generation motor is controlled to suppress an increase in the engine speed due to a decrease in the output of the drive motor.

The present invention also provides:
An engine that is driven, a power generation motor that is driven by the engine to generate electric power, a drive motor that is driven using electric power generated by the power generation motor, and a vehicle body on which the engine, the power generation motor, and the drive motor are installed A wheel connected to the vehicle body and driven by the drive motor, an overshoot predicting means for predicting an overshoot of the engine speed generated with a decrease in generated power in the generator motor, and the overshoot prediction When the means predicts that the engine speed will overshoot, the suppression means for suppressing an increase in the engine speed by correcting at least one of the engine load or the target value of the engine speed; It is an automobile characterized by comprising.

The present invention also provides:
When the power generated by the power generation motor is generated by the output of the engine and the wheels are driven by the drive motor using the power generated by the power generation motor, the engine speed exceeding the engine generated due to the decrease in power generated by the power generation motor is exceeded. When an overshoot is predicted when a shot is predicted, an increase in the engine speed is suppressed by correcting at least one of the engine load or a target value of the engine speed. This is a vehicle drive control method.

  According to the present invention, when the output of the drive motor is reduced and the generated power in the generator motor is reduced, the engine or the generator motor is controlled, and the increase in the engine speed due to the decrease in the drive motor is suppressed. Therefore, it is possible to provide a vehicle drive control device that can suppress the overshoot of the rotational speed of the power generation engine when the power generated by the power generation motor is reduced.

  Further, according to the present invention, when the overshoot predicting means predicts an overshoot of the engine speed that occurs due to a decrease in the generated power in the generator motor, the suppression means sets the engine load or the engine speed target. At least one of the values is corrected, and an increase in engine speed is suppressed. Therefore, when reducing the generated electric power of the generator motor, it is possible to provide an automobile capable of suppressing the overshoot of the rotational speed of the generator engine.

  Further, according to the present invention, when it is predicted that an engine speed overshoot will occur as the generated power in the generator motor decreases, at least one of the engine load or the engine speed target value is corrected, and the engine Suppresses the increase in rotation speed. Therefore, it is possible to provide a vehicle drive control method capable of suppressing the overshoot of the rotational speed of the power generation engine when the power generated by the power generation motor is reduced.

The best mode for carrying out the present invention (hereinafter referred to as an embodiment) will be described in detail with reference to the drawings.
(First embodiment)
First, the first embodiment will be described.
1st Embodiment is a series type hybrid vehicle carrying the vehicle drive control apparatus to which this invention is applied.

(Constitution)
FIG. 1 shows the configuration of the vehicle according to the first embodiment.
In this vehicle, drive motors 2a, 2b, 2c, and 2d are attached to the wheels 1a, 1b, 1c, and 1d, respectively, and the wheels 1a to 1d are rotationally driven by the drive motors 2a to 2d. Yes. In this vehicle, the power generation motor 5 generates power using the output torque of the power generation engine 4 driven by fuel, and the drive motors 2a to 2d are calculated by the system control unit 3 using the power supplied from the power generation motor 5. Drive output value (target drive force) is generated.

In addition, this vehicle is equipped with wheel speed detectors 6a, 6b, 6c, and 6d that detect the wheel rotation speeds of the wheels 1a to 1d, that is, detect the vehicle speed. Detection values of the wheel speed detection units 6 a to 6 d are input to the system control unit 3.
In addition, this vehicle is equipped with an accelerator pedal operation amount detection unit 7 that detects an operation amount of an accelerator pedal (not shown) by a driver (operator). The detection value of the accelerator pedal operation amount detection unit 7 is input to the system control unit 3.

In addition, this vehicle is equipped with a voltage detector 8 that detects the power supply voltage of the system. Further, this vehicle is equipped with a secondary battery 9. In this vehicle, the generated power of the generator motor 5 is corrected by the secondary battery 9. For example, the secondary battery 9 is charged with surplus power or drives the drive motors 2a to 2d with the charged power.
The system control unit 3 calculates a drive output value based on the input value (wheel speed signal) from the wheel speed detection units 6a to 6d and the input value (accelerator operation amount signal) from the accelerator pedal operation amount detection unit 7. .

FIG. 2 is a diagram showing the configuration of the series hybrid vehicle as a control function.
As shown in FIG. 2, a series hybrid vehicle shown as a control function includes a torque command calculation unit 21, a power generation control unit 24, an engine control unit 25, a drive motor 26 (drive motors 2a to 2d), and a power generation motor 27 (a power generation motor). 5) and a power generation engine 28 (power generation engine 4), a generated power reduction degree processing unit 29, an engine overshoot rotation speed calculation unit 30, a surplus generated power calculation unit 31, and a voltage detection unit 32 (voltage detection unit 8). . In addition, the system controller includes the torque command calculation unit 21, the power generation control unit 24, the engine control unit 25, the generated power reduction degree processing unit 29, the engine overshoot rotation speed calculation unit 30, the surplus generated power calculation unit 31, and the voltage detection unit 32. 3 is configured.

In such a configuration, the torque command calculation unit 21 receives the accelerator operation amount signal Si1 from the accelerator pedal operation amount detection unit 7 and the wheel speed signal Si2 from the wheel speed detection units 6a to 6d. The torque command calculation unit 21 calculates a drive output value (torque command value, target drive force) based on these input signals Si1 and Si2.
The characteristic diagram in the torque command calculation unit 21 in the figure is a table showing the relationship between vehicle speed and torque using the throttle opening as a parameter. The torque command calculation unit 21 refers to such a table. Then, a drive output value (torque command value) Si3 is calculated based on the input signals Si1 and Si2. The torque command calculation unit 21 outputs the calculated drive output value Si3 to the power generation control unit 24, the engine control unit 25, and the drive motor 26.

  The power generation control unit 24 calculates a generated power value (power generation output value or power generation command value) Si4 based on the input drive output value Si3, and outputs the calculated generated power value Si4 to the power generation motor 27. Further, the engine control unit 25 calculates an engine speed target value (output command value or target engine speed) Si5 based on the input drive output value Si3, and uses the calculated engine speed target value Si5 for power generation. Output to the engine 28.

  The drive control of the drive motor 26 is performed so that the drive output value Si3 is output from the torque command calculation unit 21. On the other hand, the drive of the generator motor 27 is controlled so that the generated power value Si4 output from the power generation control unit 24 is obtained, and the power generation engine 28 is driven by the engine rotation output from the engine control unit 25. The engine speed is controlled so as to be the numerical target value Si5.

  The generated power reduction degree processing unit 29 determines whether or not the generated power is decreasing, and calculates the reduction degree of the generated power. Specifically, the generated power reduction degree processing unit 29 determines whether or not the generated power value Si4 output from the power generation control unit 24 to the generator motor 27 is decreasing, and the generated power value Si4 is determined as the determination result. When the decrease result is obtained, the decrease degree of the generated power value Si4 is calculated. When the generated power reduction degree processing unit 29 calculates the generated power reduction degree, it outputs the generated power reduction degree to the engine overshoot speed 30.

  The engine overshoot rotational speed calculation unit 30 calculates (predicts) the overshoot rotational speed of the power generation engine 28. Specifically, the engine overshoot rotational speed calculation unit 30 includes a power generation power reduction degree input from the power generation power reduction degree processing unit 29, an engine speed target value output from the engine control unit 25 to the power generation engine 28, and an engine. Based on the current engine speed (actual engine speed or current engine speed) of the control unit 25, the engine speed (hereinafter, the engine speed calculated here is referred to as “engine overshoot speed”) is calculated. To do.

The surplus generated power calculation unit 31 calculates a surplus generated power value. Here, the surplus generated power value is a value added to the generated power value Si4 output to the generator motor 27 by the power generation control unit 24, that is, a value for increasing and correcting the output of the generator motor 27. The surplus generated power calculation unit 31 outputs the calculated surplus generated power value to the voltage detection unit 32.
The voltage detection unit 32 detects (predicts) the system voltage based on the surplus generated power value input from the surplus generated power calculation unit 31.

FIG. 3 is a flowchart showing a control procedure with the above configuration.
As shown in FIG. 3, when the process is started, in step S1, the generated power reduction degree processing unit 29 determines whether or not the generated power is decreasing. Here, if the generated power reduction degree processing unit 29 determines that the generated power is decreasing, the process proceeds to step S2.
In step S <b> 2, the generated power reduction degree processing unit 29 calculates the reduction degree of the generated power, and outputs the calculated generated power reduction degree to the engine overshoot rotational speed calculation unit 30.

Subsequently, in step S3, the current engine speed of the power generation engine 28 is input to the engine overshoot rotational speed calculation unit 30, and in the subsequent step S4, the engine control unit 25 transmits the power generation engine to the engine overshoot rotational speed calculation unit 30. The current engine output command value (engine speed target value Si5) to be output to 28 is input.
Subsequently, in step S5, the engine overshoot rotational speed calculation unit 30 calculates (predicts) the engine overshoot rotational speed based on the input power generation reduction degree, the current engine rotational speed, and the current engine output command value.

  Subsequently, in step S6, the engine overshoot rotational speed calculation unit 30 determines whether or not the engine overshoot rotational speed calculated (predicted) in step S5 needs to be attenuated (increase suppression). For example, the determination of whether or not the engine overshoot rotational speed needs to be attenuated is made by comparing the engine overshoot rotational speed with a normal engine rotational speed (for example, the average value of the latest engine rotational speed within a predetermined time) When the engine overshoot speed is increased by a predetermined value (for example, the speed acquired as an experimental value or an empirical value from the viewpoint of driver discomfort or engine load) than the normal engine speed, the engine overshoot speed Judge that the number needs to be attenuated.

If it is determined in step S6 that the engine overshoot rotational speed needs to be attenuated, the process proceeds to step S7. If it is determined that the engine overshoot rotational speed is not attenuated, the process shown in FIG. The process is started again from S1, and so on.
In step S7, the surplus generated power calculation unit 31 calculates a surplus generated power value for attenuating the engine overshoot rotational speed.

Subsequently, in step S8, the voltage detection unit 32 calculates a rising system voltage value based on the surplus generated power value calculated in step S7. Here, the increased system voltage value is the increased system voltage value (estimated value) when a value obtained by adding the surplus generated power value to the generated power value Si4 is input to the generator motor 27.
The system voltage value is an allowable voltage value of the power supply system (power consumption system). For example, when the vehicle is equipped with the secondary battery 9 as in the present embodiment, the secondary battery This results in a chargeable voltage value of 9.

Subsequently, in step S9, the voltage detection unit 32 determines whether or not the increased system voltage value calculated in step S8 is less than the allowable system voltage value. If the rising system voltage value is less than the allowable system voltage value, the process proceeds to step S10. If the rising system voltage value is equal to or greater than the allowable system voltage value, the process proceeds to step S11.
In step S <b> 10, the surplus generated power value is output (added) from the power generation control unit 24 to the power generation motor 27. For example, when an addition command is input from the voltage detection unit 32 to the power generation control unit 24, the power generation control unit 24 outputs a value obtained by adding the surplus power generation value to the power generation power value Si <b> 4 to the power generation motor 27. Then, the process shown in FIG. 3 ends.

  In step S <b> 11, as in step S <b> 10, the surplus generated power value is output from the power generation control unit 24 to the power generation motor 27. In the subsequent step S12, the surplus drive output value is output (added) to the drive motor 26. For example, the voltage detection unit 32 outputs a surplus drive output value (addition value), the surplus drive output value is added to the drive output value Si3 output by the torque command calculation unit 21 by the addition unit 33, and the addition value is obtained. Output to the drive motor 26. Then, the process shown in FIG. 3 ends.

(Operation)
Next, the operation will be described.
In this vehicle (vehicle drive control device), power is generated by the power generation motor 5 by the output torque of the power generation engine 4, and the drive motors 2 a to 2 d are driven by the generated power, and the drive calculated by the system control unit 3 is performed. Generate an output value. That is, the torque command calculation unit 21 calculates a drive output value based on the accelerator operation amount signal Si1 and the wheel speed signal Si2. Then, the engine control unit 25 calculates an engine rotation speed target value based on the drive output value calculated by the torque command calculation unit 21, and the power generation engine 28 rotates the engine so that the engine rotation speed target value is reached. The number is controlled. In addition, the power generation control unit 24 calculates a generated power value based on the drive output value calculated by the torque command calculation unit 21, and the power generation motor 27 is driven so as to have the generated power value. Then, the drive motors 2a to 2d are driven so as to have the drive output value calculated by the torque command calculation unit 21 by being supplied with the power generated by the power generation motor 27 so as to have the generated power value.

  Then, when the generated power reduction degree processing unit 29 determines that the generated power is decreasing (in the case of “Yes” in the determination of step S1), the engine overshoot rotational speed calculation unit 30 determines the generated power reduction degree. When the engine overshoot speed is calculated based on the current engine speed and the current engine output command value and it is determined that the calculated engine overshoot speed needs to be attenuated (steps S2 to S5). In the case of “Yes” in the determination in step S6, the surplus generated power calculation unit 31 calculates a surplus generated power value (step S7).

  Subsequently, the voltage detection unit 32 calculates the rising system voltage value based on the surplus generated power value, and determines whether the calculated rising system voltage value is less than the allowable system voltage value (step S9). . Here, when the rising system voltage value is less than the allowable system voltage value, an addition value of the surplus generated power value and the generated power value is output from the power generation control unit 24 to the power generation motor 27 (“Yes” in the determination of step S9). In the case of step S10), on the other hand, when the rising system voltage value is larger than the allowable system voltage value, the power generation control unit 24 outputs the added value of the surplus generated power value and the generated power value to the generator motor 27. Then, the sum of the surplus drive output value and the drive output value is output to the drive motor 26 (if the determination in step S9 is “No”, step S11, step S12).

(Function)
Next, the operation will be described.
When it is determined that the generated power is reduced and the engine overshoot rotational speed needs to be attenuated, the surplus generated power value is calculated, and the increased system voltage value by the calculated surplus generated power value is less than the allowable system voltage value. In this case, the amount of power generated by the power generation motor 27 is increased by adding the surplus power generation value to the power generation power value so as to correct the drive state of the power generation motor 27 in a direction that suppresses the decrease in power generation power. Since the load of the power generation engine 28 increases due to the increase in the amount of power generated by the power generation motor 27, an increase in the engine speed of the power generation engine 28 is suppressed, and an overshoot of the engine speed of the power generation engine 28 (engine Overshoot rotation speed) is suppressed.

  Further, when the power generation amount of the power generation motor 27 is increased in this way, the system voltage increases. For this reason, when it is determined that the generated power is reduced and the engine overshoot rotational speed needs to be attenuated, the surplus generated power value is calculated, and the increased system voltage value based on the calculated surplus generated power value is In the case of an allowable system voltage value or more, in addition to increasing the amount of power generated by the generator motor 27 by adding the surplus generated power value to the generated power value, adding the surplus drive output value to the drive output value, The driving force by the driving motor 26 is increased. Since power is consumed by driving the drive motor 26, the driving force by the drive motor 26 is increased and the power consumption is increased in this way, thereby preventing overshoot of the engine speed as described above. By increasing the power generation amount of the generator motor 27 as an object, it is possible to prevent the system voltage value from exceeding the allowable system voltage value.

  In the description of the first embodiment, the power generation motor 5 (power generation motor 27) is connected to the output shaft of the engine to realize a power generation motor that generates power by the engine, and the drive motors 2a to 2d (drives) The motor 26) realizes a drive motor that drives the wheels using the electric power generated by the generator motor, and the engine overshoot rotational speed calculation unit 30 predicts the occurrence of overshoot of the engine rotational speed. The overshoot predicting means is realized, and the process of step S10 or step S11 suppresses an increase in the engine speed when the overshoot predictor predicts that the engine speed will overshoot. Realize the means.

(effect)
(1) When the overshoot predicting means predicts an overshoot of the engine speed that occurs with a decrease in the generated power in the generator motor, the suppression means corrects the engine load (generated power of the generator motor), An increase in engine speed is suppressed. Therefore, it is possible to suppress the overshoot of the rotational speed of the power generation engine when the power generated by the power generation motor is reduced.

(2) The surplus generated power value is added to the generated power value, and the drive state of the generator motor 27 is corrected so as to suppress the decrease in the generated power. Thereby, it is possible to prevent the engine speed from overshooting with a simple configuration in which the surplus generated power value is added to the generated power value.
(3) When the control means generates surplus power corresponding to the overshoot of the engine speed, when the system power becomes lower than the system allowable voltage, the surplus power is generated by the power generation motor, which becomes a load on the power generation engine. The overshoot of the engine speed can be suppressed by the power generation operation of the power generation motor.

(4) When the control means exceeds the system allowable voltage when surplus electric power corresponding to the overshoot of the engine speed is generated in the generator motor, the electric power exceeding the system allowable voltage is transmitted at any location in the host vehicle. Since it is consumed, even if the system voltage has no margin, overshooting of the engine speed can be suppressed by the power generation operation of the power generation motor serving as the load of the power generation engine.

(5) Since the occurrence of overshoot is predicted based on the reduction degree of the generated power of the generator motor, the target engine speed and the current engine speed, the overshoot can be predicted according to the engine characteristics. .
(6) As the output of the drive motor decreases and the generated power in the generator motor decreases, the engine or generator motor is controlled, and an increase in engine speed due to the decrease in the drive motor is suppressed. Therefore, it is possible to provide a vehicle drive control device that can suppress the overshoot of the rotational speed of the power generation engine when the power generated by the power generation motor is reduced.

(7) When the overshoot predicting means predicts an overshoot of the engine speed that occurs as the generated power in the generator motor decreases, at least one of the engine load or the engine speed target value is suppressed by the suppressing means. Is corrected, and an increase in engine speed is suppressed. Therefore, when reducing the generated electric power of the generator motor, it is possible to provide an automobile capable of suppressing the overshoot of the rotational speed of the generator engine.

(8) When it is predicted that an engine speed overshoot will occur as the generated power in the generator motor decreases, at least one of the engine load or the engine speed target value is corrected to increase the engine speed. Suppress. Therefore, it is possible to provide a vehicle drive control method capable of suppressing the overshoot of the rotational speed of the power generation engine when the power generated by the power generation motor is reduced.

(Second Embodiment)
Next, a second embodiment will be described.
The second embodiment is also a series hybrid vehicle to which the present invention is applied.
(Constitution)
FIG. 4 shows the configuration of the vehicle according to the second embodiment.
As shown in FIG. 4, the vehicle of the second embodiment is different from the vehicle of the first embodiment shown in FIG. 1 in that the surplus generated power calculation unit 31 and the voltage detection unit 32 (voltage detection unit 8). ) Is gone. Further, in the vehicle of the second embodiment, the engine control unit 40 has a unique configuration, and FIG. 5 shows the configuration of the engine control unit 40 in the second embodiment. In the following description, in the vehicle of the second embodiment, the same reference numerals as those of the vehicle of the first embodiment are the same unless otherwise specified.

As shown in FIG. 5, the engine control unit 40 includes an engine speed target value calculation unit 41, a subtraction unit 42, a control calculation unit 43, an addition unit 44, and a restriction unit 45.
In such a configuration, in the engine control unit 40, the drive output value Si3 calculated by the torque command calculation unit 21 is input to the engine speed target value calculation unit 41.
The engine speed target value calculation unit 41 calculates an engine speed target value Si5 based on the input drive output value Si3, and outputs the calculated engine speed target value Si5 to the subtraction unit 42.

The subtraction unit 42 receives the current engine speed of the power generation engine 28. The subtraction unit 42 subtracts the current engine speed from the engine speed target value Si5 and obtains the subtraction value (difference value). Output to the control calculation unit 43.
The control calculation unit 43 is configured to realize so-called PID control. That is, in the control calculation unit 43, the subtraction value is input to the integration element K _I · Ｐdt, the proportional element K _P , and the differentiation element K _D · d / dt and added by the addition unit 44.

  The value added by the adding unit 44 is input to the limiting unit 45. The limiting unit 45 cuts the negative value and outputs only the positive command value, and the throttle command value Si7. To the power generation engine 28. The engine speed of the power generation engine 28 is controlled so as to be the throttle command value Si7 output from the engine control unit 40 (limit unit 45).

FIG. 6 is a flowchart showing a control procedure in the second embodiment.
The processing configuration in the second embodiment shown in FIG. 6 overlaps with the processing configuration in the first embodiment shown in FIG. 3, but in the second embodiment, the processing configuration shown in FIG. As a difference from the first embodiment, step S21 is provided instead of step S7 to step S12. In the following description, in the processing in the second embodiment, the same reference numerals as those in the processing in the first embodiment are the same unless otherwise specified.

As shown in FIG. 6, when it is determined in step S6 that the engine overshoot rotational speed needs to be attenuated, the process proceeds to step S21, and when it is determined that the engine overshoot rotational speed is not attenuated, 6 is terminated (the process is started again from step S1, and so on).
In step S21, the integral control gain is increased. Specifically, the integral gain K _I of the integral element K _I · ∫dt is increased. Then, the process shown in FIG. 6 ends.

(Operation)
Next, the operation will be described.
In this vehicle (vehicle drive control device), as in the first embodiment, the generator motor 5 generates power using the output torque of the generator engine 4, and the drive motors 2a to 2d are driven by the generated power. Then, a drive output value calculated by the system control unit 3 is generated. That is, the torque command calculation unit 21 calculates a drive output value based on the accelerator operation amount signal Si1 and the wheel speed signal Si2. Then, the engine control unit 25 calculates an engine rotation speed target value based on the drive output value calculated by the torque command calculation unit 21, and the power generation engine 28 rotates the engine so that the engine rotation speed target value is reached. The number is controlled. In addition, the power generation control unit 24 calculates a generated power value based on the drive output value calculated by the torque command calculation unit 21, and the power generation motor 27 is driven so as to have the generated power value. Then, the drive motors 2a to 2d are driven so as to have the drive output value calculated by the torque command calculation unit 21 by being supplied with the power generated by the power generation motor 27 so as to have the generated power value.

  Similarly to the first embodiment, when the generated power reduction degree processing unit 29 determines that the generated power is decreasing (in the case of “Yes” in the determination of step S1), the engine overshoot rotational speed Whether the calculation unit 30 calculates the engine overshoot speed based on the generated power reduction degree, the current engine speed, and the current engine output command value, and whether or not the calculated engine overshoot speed needs to be attenuated Is determined (step S2 to step S6).

And especially in 2nd Embodiment, the engine control part 40 is comprised as what is called a PID control system, and when it determines with attenuation | damping of an engine overshoot rotational speed is required, the engine control part 25 integral element _K integral control gain of the _I · _{∫dt K I} the increase in (in the case of "Yes" in the determination of the step S6, step S21).

(Function)
Next, the operation will be described.
When it is determined by the limiting unit 45 that the limiting unit 45 outputs only the positive throttle command value Si7 to the power generation engine 28, the engine control unit 40 determines that the engine overshoot rotational speed needs to be attenuated. and by increasing the integral control gain _{K I} of the integral element _{K I} · ∫Dt realizing the PID control in the control unit 25. That is, the engine speed is feedback-controlled by integral calculation, and the gain that acts on the decrease side of the engine speed in the integral calculation is increased. Thereby, the reduction of the throttle command value for the power generation engine 28 is accelerated. Thus, by speeding up the decrease in the throttle command value, it is possible to suppress an increase in the engine speed of the power generation engine 28 at an early stage and prevent overshoot.

The present invention can also be realized by the following configuration.
That is, by increasing the integral gain K _I, instead of faster decrease of the throttle command value, the throttle command value (engine speed target value) for a predetermined time, it is also possible to substantially zero.
Also, increasing the integral control gain K _I, a throttle command value (engine speed target value) for a predetermined time, it is made substantially zero, even the combination of adding a surplus generated power value to the generator power value Si4 it can.

(effect)
(1) When the overshoot of the engine speed generated with the decrease in the generated power in the generator motor is predicted by the overshoot predicting means, the target value of the engine speed is corrected by the suppressing means, and the engine speed Increase is suppressed. Therefore, it is possible to suppress the overshoot of the rotational speed of the power generation engine when the power generated by the power generation motor is reduced.

(2) The engine speed is feedback-controlled by integral calculation, and the gain that acts on the decrease side of the engine speed in the integral calculation is increased. Thereby, by speeding up the decrease in the target value of the engine speed, an increase in the engine speed of the power generation engine 28 can be suppressed at an early stage, and overshooting can be prevented.
(3) The engine speed target value is set to substantially zero for a predetermined time. As a result, the reduction in the target value of the engine speed can be further increased, and an increase in the engine speed of the power generation engine 28 can be suppressed at an early stage to prevent overshoot.

(Example)
FIG. 7 is an example corresponding to the first embodiment, that is, shows the change over time in the rotational speed of the power generation engine when the surplus power generation value is output to the power generation motor 27.
FIG. 4A shows changes over time in the target engine speed and the current engine speed, and the solid line shows changes over time in the current engine speed obtained by applying the present invention (the first embodiment). The dotted line shows the change over time of the current engine speed in the prior art.
FIG. 5B shows the change over time in the generated power value (generated power command value), the solid line shows the result obtained by applying the present invention (the first embodiment), and the dotted line shows The result in a prior art is shown.

  As shown in FIG. 5B, when the present invention is applied and the generated power value is decreasing, the surplus generated power value is output to the generator motor 27, so that compared with the prior art, As a result, the generated power value increases, and as shown in FIG. 5A, the current engine speed does not increase (overshoot) as in the prior art, but decreases following the engine speed target value. Will come to do.

1 is a diagram illustrating a configuration of a vehicle according to a first embodiment of the present invention. It is a figure which shows the structure of the vehicle of the said 1st Embodiment as a control function. It is a flowchart which shows the control procedure in the said 1st Embodiment. It is a figure which shows the structure of the vehicle of the 2nd Embodiment of this invention as a control function. It is a flowchart which shows the process sequence of an engine control part. It is a block diagram which shows the structure of the engine control part in the said 2nd Embodiment. It is a flowchart which shows the control procedure in the said 2nd Embodiment. It is a characteristic view which shows the time-dependent change of the present engine speed etc. which were obtained as an Example.

Explanation of symbols

  1a, 1b, 1c, 1d wheel, 2a, 2b, 2c, 2d drive motor, 3 system control unit, 4 power generation engine, 5 power generation motor, 6a, 6b, 6c, 6d wheel speed detection unit, 7 accelerator pedal operation amount Detection unit, 8 voltage detection unit, 9 secondary battery, 21 torque command calculation unit, 24 power generation control unit, 25 engine control unit, 26 drive motor, 27 power generation motor, 28 power generation engine, 29 power generation power reduction degree processing unit, 30 engine overshoot speed calculator, 31 surplus generated power calculator, 32 voltage detector

Claims (11)

A generator motor connected to the output shaft of the engine and driven by the engine to generate electric power, and a drive motor for driving wheels using the electric power generated by the generator motor;
Overshoot predicting means for predicting an overshoot of the rotational speed of the engine that occurs with a decrease in generated power in the generator motor;
When the overshoot prediction means predicts that the engine speed will overshoot, the increase in the engine speed is suppressed by correcting at least one of the engine load or the target engine speed value. Suppression means;
A vehicle drive control device comprising:   The vehicle drive control device according to claim 1, wherein the suppression unit corrects the drive state of the generator motor in a direction to suppress a decrease in the generated power.   The control means causes the power generating motor to generate the surplus power when the surplus power corresponding to the overshoot of the engine speed is generated in the power generating motor, when the power is less than a system allowable voltage. The vehicle drive control device according to claim 1 or 2.   When the surplus power corresponding to the overshoot of the engine speed is generated in the power generation motor, the control means, when exceeding the system allowable voltage, the power exceeding the system allowable voltage at any location in the host vehicle The vehicle drive control device according to claim 1, wherein the vehicle drive control device is consumed.   The vehicle drive control device according to claim 1, wherein the suppression unit performs correction to reduce a target value of the engine speed.   The engine speed is feedback controlled by an integral operation, and the suppression means suppresses an increase in the engine speed by increasing a gain that acts on the decrease side of the engine speed in the integral operation. The vehicle drive control device according to claim 1, wherein the vehicle drive control device is a vehicle drive control device.   The vehicle drive control device according to claim 1, wherein the suppression unit suppresses an increase in the engine speed by correcting the engine speed target value to zero.   The overshoot prediction means predicts the occurrence of the overshoot based on a reduction degree of power generated by the generator motor, the engine speed target value, and a current engine speed. 8. The vehicle drive control device according to any one of 7 above. A generator motor connected to the output shaft of the engine and driven by the engine to generate power; and a drive motor that drives the wheels using the power generated by the generator motor;
When the output of the drive motor decreases, at least one of the engine and the generator motor is controlled to suppress an increase in the engine speed due to a decrease in the output of the drive motor. Drive control device.   An engine that is driven, a power generation motor that is driven by the engine to generate electric power, a drive motor that is driven using electric power generated by the power generation motor, and a vehicle body on which the engine, the power generation motor, and the drive motor are installed A wheel connected to the vehicle body and driven by the drive motor, an overshoot predicting means for predicting an overshoot of the engine speed generated with a decrease in generated power in the generator motor, and the overshoot prediction When the means predicts that the engine speed will overshoot, the suppression means for suppressing an increase in the engine speed by correcting at least one of the engine load or the target value of the engine speed; An automobile characterized by comprising:   When the power generated by the power generation motor is generated by the output of the engine and the wheels are driven by the drive motor using the power generated by the power generation motor, the engine speed exceeding the engine generated due to the decrease in power generated by the power generation motor is exceeded. When an overshoot is predicted when a shot is predicted, an increase in the engine speed is suppressed by correcting at least one of the engine load or a target value of the engine speed. Vehicle drive control method.

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