JPH0698411A - Device for controlling drive of electric vehicle - Google Patents

Abstract

PURPOSE:To make highly-efficient operation of an engine possible at all times. CONSTITUTION:In the case when a detected value Ne of an engine speed is not within a prescribed range in relation to a target engine speed NT (110, 112), a command value S of the opening of a throttle is increased or decreased (118, 120) and the result is outputted (114). When a detected value P of the amount of power generation is changed by this control (106, 108), a field current of a generator is controlled so that this amount P of power generation be a value being more approximate to a target amount PT of power generation (116). By repetition of these controls, the amount P of power generation of the generator becomes a value approximate to the target amount PT of power generation and the engine speed Ne becomes also a value approximate to the target engine speed NT. According to this constitution, the engine speed Ne can always be made a value belonging to the best area of fuel cost and effects of an improvement in the fuel cost, reduction of emission, etc., can be obtained.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a drive controller for controlling an engine and a generator mounted on an electric vehicle, that is, a drive controller for an electric vehicle.

[0002]

2. Description of the Related Art An electric vehicle is a vehicle whose drive source is a motor. As an electric vehicle, for example, a so-called series hybrid vehicle in which a generator is driven by an engine and a motor is driven by the output of the generator is known. FIG. 4 shows a system configuration of a series hybrid vehicle using an AC induction motor as a motor.

The system shown in this figure includes an engine 10
Is equipped with. The engine 10 is driven under the control of the ECU 12, and its output is transmitted via a speed increaser 14 to a generator 16
Are linked to. The generator 16 generates power by the output of the engine 10 under the control of the ECU 12, and gives the generated output to the rectifier 18. The rectifier 18 rectifies the power output of the generator 16 and supplies it to the inverter 20 and also to the battery 22. The inverter 20 converts the DC voltage supplied from the rectifier 18 or the battery 22 into a three-phase AC current under the control of the ECU 12, and supplies this to the motor 24. The mechanical output of the motor 24 is connected to the drive wheel 28 via the transaxle 26 and the like, and therefore the drive wheel 28 is rotationally driven by the motor 24.

The output of the system shown in this figure is controlled by the ECU 12 based on the accelerator amount and the brake amount. The ECU 12 controls the switching element O constituting the inverter 20 according to the accelerator amount and the brake amount.
N / OFF control is performed, and vector control of the current supplied to the motor 24 is performed to generate a required output torque.

Further, the ECU 12 controls the operating conditions of the engine 10 so that the engine 12 rotates in the best fuel economy range shown in FIG. The operating conditions to be controlled include, for example, the fuel injection amount, ignition timing, throttle opening, and the like. The best fuel efficiency range is, for example, 1200 rpm to 280 in a 4-cylinder engine.
It is in the range of 0 rpm. In this region, the emission of the engine 10 is usually good.

When attempting to obtain the required electric power from the generator 16 while operating the engine 10 in such high efficiency operation, the ECU 12 controls the field current of the generator 16.
By doing so, it is possible to control the amount of power generation from the generator 16 at the target value while driving the engine 10 in the best fuel economy range. Such control is described, for example, in JP-A-51-398.
It is disclosed in Japanese Patent No. 13, etc.

[0007]

However, when the power generation amount of the generator is controlled by controlling the operating conditions of the engine and the field current of the generator, the engine speed always falls within the best fuel economy range. It may not be a value. That is, the individual characteristics of the engine and the generator vary in mass production or the like, and the difference between the individual engine and the generator changes with time. If such variations and changes over time occur, the engine speed will vary even if the amount of power generation related to the target value is obtained from the generator by field control.

[0008] The present invention has been made to solve the above problems, and while always obtaining the amount of power generation related to the target value from the generator, the engine is constantly operated at a predetermined rotation speed (for example, the best fuel economy). The purpose is to enable operation (in the area).

[0009]

In order to achieve such an object, a drive control device for an electric vehicle according to the present invention is
A means for performing field control of the generator so that the output of the generator becomes the power generation target value, and when the output of the generator becomes substantially equal to the power generation target value by the field control, the engine speed becomes substantially equal to the target value for rotation. And means for controlling the operating conditions of the engine.

Further, the drive control device for an electric vehicle according to the present invention ensures that when the output of the generator deviates from the power generation target value due to the control of the operating conditions, the output of the generator becomes the power generation target value. It is characterized by comprising means for controlling the field of the generator.

[0011]

In the present invention, the field control of the generator is first performed so that the output of the generator becomes the power generation target value. As a result of performing this control, when the output of the generator becomes substantially equal to the power generation target value, control of the operating conditions of the engine is executed at that time. This control is performed so that the engine speed becomes substantially equal to the target speed value. As a result, the engine speed is set to a predetermined speed such as in the best fuel economy range while obtaining the output related to the target power value from the generator. It becomes possible to maintain the area.

Further, in the present invention, the field control of the generator is performed when the output of the generator deviates from the power generation target value due to the control of the operating conditions. This field control is executed so that the output of the generator becomes the power generation target value. As a result of such control, in the present invention, it is possible to suppress the output change of the generator due to the control of the operating conditions.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT A preferred embodiment of the present invention will be described below with reference to the drawings. The same components as those of the conventional example shown in FIGS. 4 and 5 are designated by the same reference numerals and the description thereof will be omitted.

FIG. 1 shows a control block of an apparatus according to an embodiment of the present invention. The device according to the present embodiment is
The system configuration can be realized by the configuration shown in FIG. 4, and the characteristic is mainly in the internal configuration of the ECU 12.

As shown in this figure, in this embodiment, the ECU 12 has a power generation amount determining means 30, an engine speed determining means 32, a throttle opening determining means 34, and a throttle opening adjusting means 36. . Power generation amount determining means 3
0 determines the target power generation amount of the generator 16 by referring to the map according to the catalyst bed temperature and the capacity of the battery 22. The engine speed determining means 32 determines a target speed of the engine 10 based on the target power generation amount determined by the power generation amount determining means 30. The throttle opening determination means 34 is
The throttle opening command value is determined based on the target engine speed and engine water temperature determined by the engine speed determination means 32. At this time, the throttle opening degree determining means 34 includes a power generation amount detecting means 38 attached to the generator 16.
And the output of the engine speed detecting means 40 attached to the engine 10 are executed. The power generation amount detection means 38 detects the power generation amount of the generator 16, and the engine rotation speed detection means 40 detects the rotation speed of the engine 10. The throttle opening adjustment means 36 responds to the command value given from the throttle opening determination means 34 according to the command value.
Adjust the throttle opening of.

Further, the ECU 12 includes the field current determining means 4
2 and field current adjusting means 44. The field current determining means 42 inputs the power generation target value of the generator 16 determined by the power generation determining means 30, and the power generation detecting means 38.
The field current command value of the generator 16 is determined with reference to the output of. The field current adjusting means 44 is the field current determining means 4
According to the field current command value determined by 2, the generator 1
Adjust the field current of 6.

FIG. 2 shows the ECU 12 in this embodiment.
The flow of control, particularly the flow of the throttle opening calculation routine is shown. This routine is a routine that is repeatedly executed at predetermined intervals within a period in which the engine 10 and the generator 16 are being driven.

In this routine, first, the target power generation amount P _T is calculated (100). As described above, the target power generation amount P _T is determined by the power generation amount determining means 30 based on the battery capacity and the catalyst bed temperature. Next, the target engine speed N _T is calculated by the engine speed determining means 32 (102). This value is determined based on the target power generation amount P _T determined by the power generation amount determining means 30. Further, the throttle opening degree determining means 34 calculates the basic throttle opening degree S ₀ based on the target power generation amount P _T and the engine water temperature (104). At this point, the basic throttle opening S ₀ is substituted into the throttle opening command value S.

The throttle opening determining means 34 further includes P _T
A determination is made as to whether or not −ΔP <P (106).
When this determination is satisfied, the throttle opening degree determining means 34 further determines whether or not P <P _T + ΔP (1
08). Here, P is a power generation amount detection value by the power generation amount detection means 38, and ΔP is a value indicating an allowable error of the power generation amount. That is, steps 106 and 108 are for the generator 1
6 is a determination as to whether the detected power generation amount P of 6 is within a predetermined range with respect to the target power generation amount P _T. When the power generation amount detection value P which is substantially equal to the target power generation amount P _T is obtained, the conditions of these steps 106 and 108 are both satisfied, and the subsequent steps 110 and 112 are executed.

In step 110, N _T -ΔN <
It is determined whether Ne is satisfied, and if this condition is satisfied, in step 112, Ne <N _T + ΔN
It is determined whether or not is satisfied. Here, Ne is an engine rotation speed detection value detected by the engine rotation speed detection means 40, and ΔN is a value indicating an allowable error of the rotation speed of the engine 10. Therefore, steps 110 and 1
12, the engine speed Ne is the target engine speed N _T
Is a determination as to whether or not it is within a predetermined range. At this time, the engine speed Ne of the engine 10 is equal to the target engine speed N.
If it is almost equal to _T , steps 110 and 11
Both conditions of 2 are satisfied. In this case, the subsequent step 114 is executed, and the throttle opening degree determining means 34 outputs the throttle opening degree command value S to the throttle opening degree adjusting means 36.

It is assumed that the engine water temperature changes while the detected power generation amount P and the engine speed detection value Ne are both controlled to the target values ( _PT and _NT ). Then, the basic throttle opening S ₀ calculated in step 104 changes. If the slot opening S of the engine 10 is changed without changing the field current of the generator 12, the power generation amount of the generator 16 changes and the detected value P also changes. The condition 108 is not satisfied. In this case, the field control is executed according to the change of the throttle opening S (116).

In step 116, the field current command value is calculated so as to suppress the change in the power generation amount detection value P caused by the change in the throttle opening S. When this command value is given to the field current adjusting means 44, the power generation amount of the generator 16, and thus the detected value P, changes to a value closer to the target power generation amount P _T. After execution of step 116, the process proceeds to step 114. When such field current control is executed for a predetermined cycle, at some point, steps 106 and 1
The conditions of 08 are both satisfied, and both the detected power generation amount value P and the detected engine speed Ne are in a state of matching the target value (P _T , N _T ).

When the target power generation amount P _T changes due to changes in battery capacity and catalyst bed temperature (100), the target engine speed N _T and basic throttle opening S
₀ changes (102, 104). When the change in the target power generation amount P _T is significant, the condition of step 106 or 108 is not satisfied and step 116 is executed.
In step 116, the field current of the generator 16 is controlled so that the power generation amount P of the generator is closer to the target power generation amount P _T as described above. After that, step 114 is executed, and the command value S of the throttle opening which changes due to changes in the battery capacity and the catalyst bed temperature is output.

When this cycle is repeatedly executed, the conditions of steps 106 and 108 are satisfied at some point. If these conditions are met, step 110 is executed,
If the condition is satisfied, step 11
2 is executed. At this point steps 110 and 112
If all of the conditions are satisfied, the routine proceeds to step 114, where both the detected power generation amount P and the detected engine speed Ne are in the state of matching the target value (P _T , N _T ). Target engine speed N with changes in temperature and catalyst bed temperature
If the change in _T is large, the conditions of steps 110 and 112 are not always satisfied. If the condition of step 110 is not satisfied, step 118 of increasing the command value S of the throttle opening is executed, and if the condition of step 112 is not satisfied, step 120 of decreasing the command value S of the throttle opening. Is executed.

Here, the determination condition in step 110 is that the detected engine speed Ne is the target engine speed N _T.
Since it is a determination condition relating to whether or not it is shifted downward, the engine speed is increased by increasing the command value S of the throttle opening in step 118 to reach the target engine speed N _T. It is a close value. On the contrary, the determination condition in step 112 is a determination as to whether or not the engine speed detection value Ne deviates to the upper side of the target engine speed N _T , so that the decrease in the engine speed Ne accompanying the execution of step 120 causes Step 112 gradually
The determination condition of will be met.

As described above, in this embodiment, both the amount of power generation and the engine speed are controlled so as to be equal to the target value (P _T , N _T ). This control is particularly effective in dealing with the deviation of the engine speed Ne described below. FIG. 3 shows the characteristic control contents in this embodiment.

As shown at 200 in this figure,
At a certain point in time, the power generation amount of the generator 16 is the target power generation amount P _T
If the engine speed of which is approximately equal is not equal to the target engine speed N _T in so that the engine speed becomes the target engine speed N _T by the execution of the throttle opening computing routine shown in FIG. 2 That is, the throttle opening and the field current are controlled so as to shift from the point 200 to the point 202. Such a difference in the engine speed occurs due to the difference between the individual engines 10 and the generators 16 or the change over time as described above.

Next, the contents of this control will be described according to the flow of FIG.

It is assumed that the control state is point 200 at some point. In this state, the engine speed deviates downward from the target engine speed N _T , so step 110
Is not satisfied, the command value S of the throttle opening is upwardly corrected in step 118. When the command value S of the throttle opening is output in step 114, the power generation amount P increases along the line of the large field current in FIG. Then, when the throttle opening calculation routine is executed next time, the condition of step 108 is not satisfied, and therefore step 116 relating to the field control is executed. In step 116, the field current is changed so that the power generation amount P becomes closer to the target power generation amount P _T. As a result of this control, when the power generation amount P becomes substantially equal to the target power generation amount P _T , the conditions of steps 106 and 108 are satisfied when the throttle opening calculation routine is executed next, and the process proceeds to steps 110 and 112. To do. In this state, if the engine speed Ne is not yet sufficiently close to the target engine speed N _T , step 118 is executed again and the upwardly corrected throttle opening command value S is output in step 114. It Then, along with this, the amount of power generated by the generator 16 increases again. As a result of this increase, when the conditions of steps 106 and 108 are not satisfied, step 116 relating to field control is executed again.

When such control is repeated, the point 200
From the point 202 toward the point 202, the amount of power generation and the engine speed gradually change in a sawtooth shape. The power generation amount P is sufficiently close to the target power generation amount P _T , and the engine speed Ne is the target engine speed N.
_When the state is sufficiently close to _T , that is, when the point 202 is reached, all the conditions of steps 106 to 112 are satisfied, and this control state is maintained.

As described above, according to the present embodiment, the difference in the engine speed and the difference in the engine speed caused by the time-dependent change of the engine 10 and the generator 16 are suppressed, and the generator 16 is suppressed.
It is possible to make the value almost equal to the target value together with the power generation amount. Therefore, even if the target power generation amount P _T is obtained from the generator 16, the situation in which the engine speed Ne deviates from the optimum fuel consumption range and the emission increases, or the like, is unlikely to occur.

In the above description, the throttle opening is used as the operating condition of the engine 10 to be controlled, but other operating conditions may be used.

[0033]

As described above, according to the present invention,
When the output of the generator is almost equal to the power generation target value by the field control, the engine operating conditions are controlled so that the engine speed is made to substantially match the engine speed target value.
Despite the fact that the generator produces an output that is almost equal to the target power generation value, the engine speed does not deviate from a predetermined range such as the best fuel economy range, resulting in good fuel economy and reduced emissions. Meanwhile, it becomes possible to obtain the required amount of power generation.

Further, according to the present invention, when the output of the generator deviates from the power generation target value due to the control of the operating condition, the field control of the generator controls the output of the generator to the power generation target value. Therefore, it is possible to suppress the change in the output of the generator due to the control of the power generation condition.

[Brief description of drawings]

FIG. 1 is a control block diagram of an apparatus according to an embodiment of the present invention.

FIG. 2 is a control flowchart showing a flow of a throttle opening calculation routine in this embodiment.

FIG. 3 is a diagram showing characteristic control contents in this embodiment.

FIG. 4 is a block diagram showing an example of a system configuration of an electric vehicle.

FIG. 5 is a diagram showing an engine fuel consumption best range.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 10 engine 12 ECU 16 generator 20 inverter 24 motor 30 power generation amount determining means 32 engine speed determining means 34 throttle opening determining means 36 throttle opening adjusting means 38 power generation detecting means 40 engine speed detecting means 42 field current detection Means 44 Field current adjusting means P _T target power generation amount N _T target engine speed S ₀ basic throttle opening S throttle opening command value P power generation amount detected value Ne engine speed detected value

Claims (2)

[Claims] 1. A drive control device mounted on an electric vehicle equipped with an engine, a generator for generating electric power by rotation of the engine, and a motor driven by output of the generator to generate propulsive force of the vehicle, and controlling at least the engine and generator. In the above, the means for controlling the field of the generator so that the output of the generator becomes the target value for power generation, and when the output of the generator becomes almost equal to the target value for power generation by the field control, the engine speed becomes the target value for the number of rotations. A drive control device comprising means for controlling engine operating conditions so that they are substantially equal to each other. 2. The drive control device according to claim 1, wherein when the output of the generator deviates from a power generation target value due to control of operating conditions, the field control of the generator is performed so that the output of the generator becomes the power generation target value. A drive control device comprising means for performing.