JP2000354301A - Run controller in electric vehicle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To eliminate troublesome operation of a brake pedal by using regenerative braking of a motor effectively in an electric vehicle. SOLUTION: When an accelerator is turned off, regenerative braking is not carried out or weak operation of regenerative braking is carried out in a D range according to the run conditions. In the second, first or R range, regenerative braking larger than that in the D range is carried out to obtain larger deceleration sequentially. In this way, only by stepping off the accelerator, an adequate amount of regenerative braking is applied, so that troublesome braking operation can be eliminated even at running on an up and down slope, while energy is regenerated without waste.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a travel control device for an electric vehicle that makes effective use of regenerative braking.

[0002]

2. Description of the Related Art As a conventional travel control device for an electric vehicle, for example, Japanese Patent Application Laid-Open Nos.
There is one disclosed in each publication of No. 24012.
In the former traveling control device, a reverse torque due to regenerative braking is supplied according to the operation amount of the brake pedal. Also in the latter case, the regenerative braking force of the motor can be obtained in proportion to the depression force of the brake pedal or the pedal stroke.

[0003]

However, in such a conventional traveling control device for an electric vehicle, regenerative braking is performed only when a brake is operated. In such a case, there is a problem that the driver needs to frequently operate both the accelerator pedal and the brake pedal. Accordingly, an object of the present invention is to provide a travel control device for an electric vehicle in which regenerative braking of a motor is effectively used and complicated pedal operation is not required in view of the above-described problems.

[0004]

SUMMARY OF THE INVENTION Accordingly, the present invention provides a motor for driving wheels using a battery as a power source, an accelerator device, and a control means for controlling the output of the motor based on a signal sent from the accelerator device. In the travel control device for an electric vehicle comprising: an accelerator detection means for detecting on / off of the accelerator device, and a shift lever device capable of selecting a plurality of travel ranges, wherein the control means comprises: An accelerator-off regenerative means for performing a regenerative braking at a predetermined level corresponding to the running range selected when the device is turned off is provided.

[0005]

According to the present invention, a shift lever device capable of selecting a plurality of traveling ranges is provided, and when the accelerator device is turned off, regenerative braking of a predetermined level corresponding to the traveling range selected by the shift lever device is performed. Therefore, not only when the brake pedal is operated but also when the brake pedal is not depressed, an appropriate amount of regenerative braking is applied, and even when the vehicle travels on a slope with many ups and downs, the brake operation is released from complicated operations. In addition, a sharp braking effect corresponding to the selected driving range when the accelerator is released is obtained. In addition, there is an effect that energy is recovered without waste.

[0006]

Embodiments of the present invention will be described below with reference to examples. FIG. 1 is a block diagram showing the configuration of the embodiment. The motor 1 powered by the battery 6 is driven under the control of the controller 5, and the output of the motor is transmitted from the drive shafts 3, 3 to the wheels 10, 10 via the reduction gear 2. The controller 5 is connected with an accelerator device 7, a shift lever device 9, and a brake pedal switch 8 as a brake detecting means. From the accelerator device 7, a signal indicating the operation amount of the accelerator pedal is input to the controller. Accelerator device 7
An accelerator pedal switch 12 is provided in association with the control signal, and an ON / OFF signal indicating whether the accelerator pedal is depressed or released from the accelerator pedal switch 12 is input to the controller.

The controller 5 controls the motor so as to output a necessary torque in accordance with the depression amount of the accelerator pedal, that is, the operation amount when the accelerator pedal is turned on, and has a function as control means of the invention. An on / off signal is input from a brake pedal switch 8 of a mechanical brake device such as a hydraulic pressure in response to the presence or absence of a brake operation. The shift lever device 9 has drive (D), drive 2 and drive 1 ranges as forward travel stages, and also has a neutral (N), reverse (R) and parking (P) range. A range position signal indicating which of the ranges the shift lever is engaged with is input to the controller 5. Note that the 2 and 1 ranges do not have a corresponding specific gear ratio, are the same as the D range, and only the position is set.

The controller 5 further controls regenerative braking during deceleration based on the accelerator pedal on / off signal, range position signal, and brake pedal on / off signal. In driving the motor, the controller 5 controls to change the gain of the driving force with respect to the accelerator operation amount in accordance with the range position in the shift lever device 9. The accelerator pedal switch 12 described above constitutes the accelerator detecting means of the present invention.

The control flow of regenerative braking in the controller is shown in FIGS. In step 100,
It is determined whether the vehicle is traveling or stopped by checking whether the range position in the shift lever device 9 is in either the P range or the N range. If the range is not P or N,
When the vehicle is running, it is checked in which range the vehicle is running. That is, first, the routine proceeds to step 110, where it is checked whether the range position is the drive D range. If it is in the D range, the routine proceeds to step 111, where it is checked whether or not the accelerator pedal is on.

When the accelerator pedal is off, that is, when the foot is released and released from the pedal, step 112
Proceed to. In step 112, the controller 5 sets a very small level of regenerative braking or regenerative braking so that the deceleration set in advance corresponding to the range position shown in FIG. No control is performed. In general driving in the D range, when the accelerator is turned off, the smaller the deceleration is, the more the vehicle does not jerky, so that a smooth running feeling is first obtained.

[0011] Thereafter, at step 113, it is checked whether the deceleration due to the accelerator off is not enough and the driver is operating the brake. When the brake pedal is operated and turned on, the routine proceeds to step 114, where a regenerative braking force for deceleration is added. Since the control flow is continuously repeated, when the brake pedal is depressed after the accelerator is turned off, the brake pedal switch 8 is operated before the mechanical brake is applied, and the regenerative braking force in step 114 is added. For this reason, the driver only has to lightly depress the brake pedal in accordance with the deceleration desired by the driver, in proportion to the insufficient braking force. At this time, if the added regenerative braking amount is too large, the driving feeling is degraded, so it is preferable that the added amount is appropriately small.

If the result of the check in step 111 is that the accelerator pedal is on, the flow returns to the start of the flow because braking is not particularly required. Also, in step 113, when the brake pedal is off, it is determined that further braking is unnecessary, and the flow returns to the start.

If the range position is not D in step 110, it is next checked in step 120 whether the range position is in two ranges. If it is in the two ranges, the routine proceeds to step 121, where it is checked whether or not the accelerator pedal is on. When the accelerator is released and in the off state, the routine proceeds to step 122, where regenerative braking is applied so as to achieve the "medium" level of deceleration set in FIG. This deceleration is almost the same as that obtained by selecting the third speed in a vehicle equipped with an internal combustion engine.
Then, in the next steps 123 and 124, step 11
As in 3, 114, the regenerative braking force is added when the brake pedal is turned on.

If the result of the check in step 120 is not 2 ranges, it is checked in step 130 whether the range is in the 1 range or the R range. When it is in the 1 or R range, the routine proceeds to step 131, and when the accelerator is in the off state, in step 132, regenerative braking is applied so as to achieve the "large" level deceleration shown in FIG. This is greater than the set deceleration in the two ranges, and is substantially the same as that obtained in the first, second or reverse position in the vehicle equipped with the internal combustion engine. Then, in the next steps 133 and 134, steps 113 and 11
Similarly to 4, the regenerative braking force is added when the brake pedal is turned on. Steps 111 to 112, 121 to 1
22, steps 131 to 132 constitute the accelerator-off regeneration means of the invention.

Since the embodiment is constructed as described above, regenerative braking is not performed or weak regenerative braking is performed only when the accelerator is turned off while driving in the D range, and further when the brake pedal is depressed. Additional regenerative braking is performed. When in the 2 range, 1 or R range, when the accelerator is turned off, regenerative braking larger than in the D range is performed correspondingly, and when the brake pedal is depressed in the same manner as above, the regenerative braking is further increased. Is performed.

Therefore, when the vehicle is running on a slope with many ups and downs, the accelerator pedal is operated when the brake pedal is operated, and when the accelerator is turned off even when the brake pedal is not depressed, the position of the shift lever at that time is adjusted. Since an appropriate amount of regenerative braking is applied, as in an automatic transmission in a vehicle with an internal combustion engine, coasting or moderate deceleration can be obtained with the accelerator off during normal driving in the D range, and when the accelerator is off in the low speed range and the R range. It will be a strong deceleration. As a result, there is an advantage that the operation can be performed without fatigue by being released from a complicated brake operation, and energy can be recovered without waste. On the other hand, since the gain of the driving force with respect to the accelerator is changed according to the position of the shift lever, sharp acceleration is exhibited by the accelerator operation amount, and sports running becomes easy.

The accelerator device is provided with an accelerator pedal switch so that an accelerator on / off signal is obtained from the accelerator pedal switch. However, the present invention is not limited to this. The accelerator pedal operation, which is a signal from the accelerator device, is not limited to this. If the accelerator-off is determined by checking whether the amount is zero, the accelerator pedal switch can be omitted.

[Brief description of the drawings]

FIG. 1 is a diagram showing an embodiment of the present invention.

FIG. 2 is a flowchart of control in the embodiment.

FIG. 3 is a flowchart of control in the embodiment.

FIG. 4 is a diagram illustrating an example of a set deceleration with respect to a range position of a shift lever.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Motor 2 Reduction gear 3 Drive shaft 5 Controller 6 Battery 7 Accelerator device 8 Brake pedal switch 9 Shift lever device 10 Wheel 12 Accelerator pedal switch

Claims (1)

[Claims] 1. A travel control device for an electric vehicle, comprising: a motor for driving wheels using a battery as a power source; an accelerator device; and control means for controlling the output of the motor based on a signal sent from the accelerator device. Accelerator detection means for detecting the on / off state of the accelerator device, and a shift lever device capable of selecting a plurality of traveling ranges, wherein the control means selects when the accelerator device is turned off during traveling. A travel control device for an electric vehicle, comprising accelerator-off regenerative means for performing a predetermined level of regenerative braking corresponding to the travel range being set.