WO2012114425A1

WO2012114425A1 - Display system of electric vehicle and electric vehicle equipped with same

Info

Publication number: WO2012114425A1
Application number: PCT/JP2011/053672
Authority: WO
Inventors: 山本　雅哉; 至瀬田
Original assignee: トヨタ自動車株式会社
Priority date: 2011-02-21
Filing date: 2011-02-21
Publication date: 2012-08-30

Abstract

An electric vehicle comprises a battery device (10) and an electric motor (30) receiving electric power from the battery device and generating travel driving force. A display system comprises a display device (60) for displaying vehicle information to an occupant and a control device (50) for, according to a parameter associated with the distance that the electric vehicle travels, making a display device display the boundary value dividing the inside and outside of a recommended driving area that is set in order to ensure the traveling distance of the vehicle. It is preferable for the parameter to include the state of charge of the battery device and the distance to the destination of the electric vehicle. The display system can provide information about a driving condition suitable for reaching the destination to the driver. The driver drives with reference to this information, thereby increasing the possibility of enabling the destination to be reached without charging on the way.

Description

Electric vehicle display system and electric vehicle equipped with the same

The present invention relates to an electric vehicle display system and an electric vehicle including the electric vehicle display system, and more particularly to an electric vehicle display system equipped with a power storage device that stores electric power for traveling and an electric vehicle including the electric vehicle display system.

Japanese Patent Laying-Open No. 2008-174019 (Patent Document 1) discloses a technique for performing a display for a driver to more effectively realize economic driving in a vehicle capable of selecting a fuel efficiency priority mode that prioritizes fuel efficiency. . Specifically, in the hybrid vehicle, when the ECO switch is turned on, it is determined whether or not the traveling state is the economic traveling state by using the ECO mode traveling state determination map. Then, the determination result is displayed on the meter display unit so that it is possible to identify whether or not the traveling state is the economic traveling state in the form of turning on or off the ECO mark.

JP 2008-174019 A JP 2007-304791 A

In a vehicle configured to charge an in-vehicle power storage device from the outside, for example, an electric vehicle or a plug-in hybrid vehicle, there is a great need to travel only with charged power or to travel. However, if the amount of power storage is insufficient, it may not be possible to reach the destination.

On the other hand, in such a vehicle, the distance that can be traveled varies greatly depending on the current storage amount, depending on the travel speed and the required travel power. For example, it may be possible to reach the same destination by traveling on a general road at a low speed, but when driving on a highway and traveling at a high speed, energy may be exhausted.

As described in Japanese Patent Application Laid-Open No. 2008-174019, a technique for informing the driver whether or not the current driving state is an economic driving state by turning on / off the ECO mark is also conceivable. However, in this case, it is difficult to understand what kind of travel is performed when the current travel state is not the economic operation state. Moreover, even if the vehicle is driven in an economic driving state, it is not known whether or not the destination can be reached.

An object of the present invention is to provide a display system that can provide a driver with information about an appropriate driving state in order to reach a destination, and a vehicle including the display system.

In summary, the present invention provides a display system for an electric vehicle, the electric vehicle including a power storage device and an electric motor that receives electric power from the power storage device and generates a driving force for driving. A display device for displaying information and a boundary value for separating the inside and outside of the recommended travel area set for securing the travel distance of the vehicle according to the parameter related to the distance traveled by the electric vehicle is displayed on the display device. And a control device.

Preferably, the parameter includes the distance to the destination of the electric vehicle. The control device sets the boundary value according to the distance to the destination.

Preferably, the parameter includes a state of charge of the power storage device. The control device sets the boundary value according to the state of charge of the power storage device.

Preferably, the parameters include the state of charge of the power storage device and the distance to the destination of the electric vehicle. The control device sets a boundary value according to the state of charge of the power storage device and the distance to the destination of the electric vehicle.

More preferably, the recommended travel area is determined with respect to the vehicle speed, and the boundary value indicates an upper limit speed at which the power storage device in a charged state can travel a distance.

More preferably, the display device displays the current vehicle speed and the boundary value in a manner that can be viewed at the same time.

More preferably, the recommended travel area is determined with respect to power, and the boundary value indicates an upper limit power that can be output when traveling a distance by a power storage device in a charged state.

More preferably, the display device displays the current output power and the boundary value in a manner that can be viewed simultaneously.

More preferably, the control device updates the boundary value based on the change in the state of charge of the power storage device due to traveling and the change in the distance to the destination of the electric vehicle due to traveling, and causes the display device to display the boundary value.

In another aspect, the present invention is an electric vehicle including any one of the display systems described above.

According to the present invention, it is possible to provide the driver with information on an appropriate driving state in order to reach the destination, and the driver performs driving with reference to this, so that charging is not performed on the way. However, the possibility of reaching the destination increases.

1 is an overall block diagram of an electric vehicle according to an embodiment of the present invention. It is a functional block diagram of ECU50 shown in FIG. It is a flowchart for demonstrating control about the learning of the power consumption rate (electricity cost) which ECU50 of FIG. 1 performs. It is the figure which showed an example of the change of the vehicle speed and the power consumption rate at the time of driving | running | working. It is the figure which showed an example of the power consumption rate-vehicle speed map. It is a flowchart for demonstrating the update process of the map which shows the relationship between a driving | running | working possible distance and a vehicle speed. FIG. 6 is a diagram showing an example of a travelable distance-vehicle speed map. It is a flowchart for demonstrating the process which produces | generates the information about the upper limit vehicle speed displayed on a display apparatus. It is a figure for demonstrating determining the upper limit vehicle speed Kmax from a map. It is a figure for demonstrating the change of the upper limit vehicle speed Kmax when SOC changes. It is a figure which shows the 1st example of a display which displayed the upper limit vehicle speed on the vehicle speed meter. It is a figure which shows the 2nd display example which displayed the upper limit vehicle speed on the vehicle speed meter. It is a flowchart for demonstrating the process which produces | generates the information about the upper limit power displayed on a display apparatus. It is a figure which shows the example of a display which displayed the upper limit power on the power meter.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. In the drawings, the same or corresponding parts are denoted by the same reference numerals, and description thereof will not be repeated.

FIG. 1 is an overall block diagram of an electric vehicle according to an embodiment of the present invention.
Referring to FIG. 1, electrically powered vehicle 100 includes a power storage device 10, an inverter 20, a motor generator 30, and drive wheels 35. The electric vehicle 100 further includes a voltage sensor 42, a current sensor 44, a temperature sensor 46, a wheel speed sensor 37, an electronic control device (hereinafter referred to as “ECU: Electric Control Unit”) 50, and a display device 60. including.

The power storage device 10 is a DC power source that stores electric power for running the vehicle. The power storage device 10 includes, for example, a secondary battery such as nickel metal hydride or lithium ion. The power storage device 10 is charged by a power source outside the vehicle using a charger (not shown). In addition, the electric power generated by the motor generator 30 is charged to the power storage device 10 via the inverter 20 also when the electric vehicle 100 is braked or when the acceleration on the down slope is reduced.

The power storage device 10 outputs the stored power to the inverter 20. Inverter 20 converts DC power supplied from power storage device 10 into three-phase AC based on signal PWI from ECU 50 and outputs the same to motor generator 30 to drive motor generator 30.

When the electric vehicle 100 is braked, the inverter 20 converts the three-phase AC power generated by the motor generator 30 into DC based on the signal PWI and outputs the DC power to the power storage device 10. Inverter 20 is configured by a three-phase PWM inverter including switching elements for three phases, for example.

The motor generator 30 is a motor generator capable of a power running operation and a regenerative operation. The motor generator 30 is configured by, for example, a three-phase AC synchronous motor generator in which a permanent magnet is embedded in a rotor. The motor generator 30 is driven by the inverter 20 and generates driving torque for driving to drive the driving wheels 35. In addition, when the electric vehicle 100 is braked, the motor generator 30 receives the kinetic energy of the electric vehicle 100 from the drive wheels 35 and generates electric power.

Voltage sensor 42 detects voltage VB of power storage device 10 and outputs the detected value to ECU 50. Current sensor 44 detects current IB input to and output from power storage device 10 and outputs the detected value to ECU 50. Temperature sensor 46 detects temperature TB of power storage device 10 and outputs the detected value to ECU 50. The wheel speed sensor 37 outputs a pulse generated with the rotation angle of the drive wheel 35. The ECU 50 can count the number of pulses to calculate the travel distance L and the vehicle speed. Note that the moving distance and the vehicle speed may be obtained by detecting the rotational speed of the motor generator 30 instead of the wheel speed sensor 37.

ECU 50 receives detected values of voltage VB, current IB, and temperature TB from voltage sensor 42, current sensor 44, and temperature sensor 46, respectively. Then, ECU 50 generates a PWM signal for driving inverter 20 and outputs the generated PWM signal to inverter 20 as signal PWI.

Further, the ECU 50 calculates the SOC (State Of Charge: also referred to as a state of charge, a remaining capacity, and a storage amount) of the power storage device 10 based on the detected values of the voltage VB and the current IB. As a calculation method of the SOC, there are various known methods such as a calculation method using the relationship between the open circuit voltage (OCV) of the power storage device 10 and the SOC and a calculation method using the integrated value of the current IB. Can be used.

The display device 60 displays information on a distance that can be traveled using the current power storage amount of the power storage device 10 when the vehicle is started or during travel based on the signal DISP from the ECU 50. This information includes an appropriate vehicle speed range or vehicle speed upper limit value, an appropriate power range or power upper limit value, and the like.

FIG. 2 is a functional block diagram of the ECU 50 shown in FIG. In FIG. 2, only the functions of the portions related to the display control of the display device 60 are shown.

Referring to FIG. 2, ECU 50 includes an SOC calculation unit 110, a power consumption detection unit 120, a vehicle speed detection unit 130, a display control unit 140, a storage unit 150, and a planned travel distance detection unit 160.

The SOC calculation unit 110 calculates the SOC of the power storage device 10 based on the detected values of the voltage VB and the current IB of the power storage device 10, and outputs the calculated value SC to the display control unit 140. For calculating the SOC, various known methods such as a method of calculating using the relationship between the OCV and the SOC of the power storage device 10 and a method of calculating using the integrated value of the current IB can be used.

The power consumption detection unit 120 receives the detection value of the voltage VB and the detection value of the current IB, calculates the power consumption by multiplying them, and stores the power consumption in the storage unit 150. The vehicle speed detection unit 130 detects the vehicle speed based on the signal L from the wheel speed sensor 37 and stores it in the storage unit 150 together with the power consumption obtained by the power consumption detection unit 120.

The scheduled travel distance detection unit 160 acquires the distance D to the destination from a car navigation device (not shown), for example, and stores it in the storage unit 150.

The display control unit 140 receives information indicating the relationship between the vehicle speed and the power consumption from the storage unit 150 according to a signal IGON indicating that the vehicle has started, or a trigger signal generated at regular time intervals, Information indicating the distance D is read. Based on this information and the SOC given from the SOC calculation unit 110, the display control unit 140 displays information on the optimum travel distance and travel power for reaching the destination without additional charging. A control signal DISP for display on the device 60 is output.

FIG. 3 is a flowchart for explaining the control of learning of the power consumption rate (electric cost) executed by the ECU 50 of FIG. The power consumption rate is also referred to as a power consumption, and is an index indicating how much power can be traveled over a certain distance, and (Wh / km) is a unit.

FIG. 4 is a diagram showing an example of changes in vehicle speed and power consumption rate during traveling.
Referring to FIGS. 3 and 4, when the process is started, in step S <b> 1, ECU 50 obtains or calculates travel distance L and vehicle speed K based on the output of wheel speed sensor 37, voltage sensor 42 and current. Based on the detection value of the sensor 44, the power consumption P (= IB × VB) is obtained or calculated.

Subsequently, the ECU 50 calculates a power consumption rate (Wh / km) per traveling section or traveling time.

In FIG. 4, the average value P1 of the electric power consumption is calculated with respect to the average value K1 of the vehicle speed from time 0 to t1. Similarly, average values P2 to P8 of power consumption are obtained corresponding to the average values K2 to K8 of the vehicle speed in each traveling section. In addition, the division | segmentation of each driving | running | working area may be for every fixed driving time, and may be for every fixed driving distance.

FIG. 5 is a diagram showing an example of the power consumption rate-vehicle speed map.
In FIG. 5, the power consumption rate (Wh / km) is plotted on the vertical axis, and the vehicle speed (km / h) is plotted on the horizontal axis. For example, when the traveling up to time t1 is completed, data of the vehicle speed K1 and the power consumption rate P1 are plotted on the coordinate plane of FIG. Then, in step S4 of FIG. 3, it is determined whether or not the trip end has occurred. A trip means a unit of movement of a vehicle. For example, in the case of commuting, one trip in which the vehicle is started and moved in the morning, arrives at the commuting destination and gets off the vehicle is called one trip. The trip end means that the vehicle is moved after being started and the vehicle is turned off.

If it is not yet a trip end, steps S1 to S3 are executed again. By repeating the processing of steps S1 to S3 in this way, power consumption rates P2 to P8 corresponding to the vehicle speeds K2 to K8 are plotted on the coordinate plane of FIG. If it is determined in step S4 that the trip has ended, the process proceeds to step S5.

In step S5, the power consumption rate-vehicle speed map is corrected. In FIG. 5, a point newly added to the plot is processed by a known approximation method such as a least square method to draw one graph. This is stored in the storage unit 150. Thereafter, assuming that the trip has ended, the process ends in step S6. It is also possible to store the power consumption rate and vehicle speed data and obtain the graph when the vehicle is started.

FIG. 6 is a flowchart for explaining a map update process indicating the relationship between the travelable distance and the vehicle speed. The process of this flowchart is called and executed from a predetermined main routine every predetermined time or every time a predetermined condition is satisfied.

Referring to FIG. 6, when the process is first started, ECU 50 acquires the amount of power stored in power storage device 10 in step S <b> 11. For example, the SOC calculation unit 110 shown in FIG. 2 reads what is stored in the storage unit 150 at the end of the previous run. Further, this SOC (%) is converted into usable electric energy (Wh).

Subsequently, in step S12, the ECU 50 calculates the travelable distance for each vehicle speed using the calculated usable electric energy and the power consumption rate for each vehicle speed obtained in FIG. -Update the vehicle speed map. When the map update is completed, control is returned to the main routine in step S13.

FIG. 7 is a diagram showing an example of a travelable distance-vehicle speed map.
Referring to FIG. 7, the vertical axis indicates the distance (km) that can be traveled without energy supply such as additional charging, and the horizontal axis indicates the vehicle speed (km / h). A map MAP1 when the SOC is A1 and a map MAP2 when the SOC is A2 are shown. A2 <A1.

In both maps MAP1 and MAP2, the possible travel distance decreases as the vehicle speed increases. That is, when the vehicle travels at a high vehicle speed, the power consumption rate deteriorates, and the travelable distance is greatly reduced.

Then, after traveling for a while from the state where the SOC of the power storage device 10 is A1, the map is updated from the map MAP1 to the map MAP2 when the SOC of the power storage device 10 decreases to A2.

FIG. 8 is a flowchart for explaining processing for generating information on the upper limit vehicle speed to be displayed on the display device. The process of this flowchart is called and executed from a predetermined main routine every predetermined time or every time a predetermined condition is satisfied.

Referring to FIG. 8, when the process is started, ECU 50 calculates the remaining distance to the destination in step S21. As the remaining distance, for example, the distance D acquired by the planned travel distance detection unit in FIG. 2 and stored in the storage unit 150 from the car navigation device can be used.

Subsequently, in step S21, the ECU 50 calculates an upper limit vehicle speed Kmax for reaching the destination without additional charging from the travelable distance-vehicle speed map described in FIG.

FIG. 9 is a diagram for explaining the determination of the upper limit vehicle speed Kmax from the map.
Referring to FIG. 9, if a straight line parallel to the horizontal axis is drawn on the map so as to correspond to the distance to the destination, upper limit vehicle speed Kmax can be obtained from the coordinates of the intersection.

FIG. 10 is a diagram for explaining a change in the upper limit vehicle speed Kmax when the SOC changes.

Referring to FIG. 10, it is assumed that the map is initially map MAP1 and the upper limit vehicle speed is Kmax.

As a result of traveling while maintaining the upper limit vehicle speed Kmax, if the SOC decreases with time, the map is updated from the map MAP1 to the map MAP2. At this time, since the distance to the destination has also decreased due to running, the horizontal line corresponding to the distance has also moved downward. As a result, the upper limit vehicle speed Kmax2 obtained from the coordinates of the intersection is substantially equal to the upper limit vehicle speed Kmax before the map update.

However, when the vehicle travels at a vehicle speed higher than the upper limit vehicle speed Kmax, the rate of decrease in SOC increases with a decrease in distance. In this case, the map is updated from the map MAP1 to the map MAP3. The upper limit vehicle speed Kmax3 is obtained from the intersection. The upper limit vehicle speed Kmax3 is lower than the upper limit vehicle speed Kmax before update.

Referring to FIG. 8 again, after the upper limit vehicle speed Kmax is obtained in step S22 as described in FIG. 10, the upper limit vehicle speed Kmax is displayed on the vehicle speed meter in step S23, and in step S24, the control is performed by the main routine. Returned.

FIG. 11 is a diagram showing a first display example in which the upper limit vehicle speed is displayed on the vehicle speed meter.
In the example shown in FIG. 11, the color of the band-shaped background region along the locus along which the tip of the pointer indicating the vehicle speed K moves is configured to be changeable. The background area is displayed so that the color of the portion indicating the vehicle speed 0 to Kmax is different from the color of the portion indicating the vehicle speed higher than the vehicle speed Kmax. Any display may be used as long as the upper limit vehicle speed Kmax can be identified as the boundary value. However, it is preferable that the color of the portion showing the vehicle speed higher than the vehicle speed Kmax is displayed lighter than the color of the portion showing the vehicle speed 0 to Kmax. Alternatively, the color may be changed by changing the color of the portion showing the vehicle speed 0 to Kmax to green and changing the color of the portion showing the vehicle speed higher than the vehicle speed Kmax to red.

FIG. 12 is a diagram showing a second display example in which the upper limit vehicle speed is displayed on the vehicle speed meter.
The example shown in FIG. 12 displays the vehicle speed K in a digital display. In this example, 36 km / h is displayed as the current vehicle speed K with a large number, and 70 km / h is displayed as the upper limit vehicle speed Kmax with a small number beside it.

It is preferable that the display device displays the current vehicle speed and the boundary value indicating the upper limit vehicle speed in a manner that can be viewed simultaneously. As a result, the driver can easily travel so as not to exceed the upper limit vehicle speed by adjusting the degree of depression of the accelerator pedal.

In the foregoing, the example in which the upper limit vehicle speed Kmax is displayed on the display device in a manner that can be viewed simultaneously with the current vehicle speed K has been described. Instead of the upper limit vehicle speed or in addition to the upper limit vehicle speed, the current output power and the upper limit output power may be displayed on the display device.

FIG. 13 is a flowchart for explaining a process of generating information about the upper limit power to be displayed on the display device. The process of this flowchart is called and executed from a predetermined main routine every predetermined time or every time a predetermined condition is satisfied.

Referring to FIG. 13, when the process is started, in step S31, ECU 50 arrives at the destination based on the remaining distance to the destination and upper limit vehicle speed Kmax obtained in the process of FIG. The travel time is calculated. In a simple example, the travel time can be obtained by dividing the distance D by the upper limit vehicle speed Kmax.

In step S32, the ECU 50 calculates the upper limit power Pmax from the current SOC and the travel time obtained in step S31. In a simple example, the upper limit power Pmax (W) can be calculated by dividing the available electric energy (Wh) corresponding to the SOC by the travel time (h).

In step S33, the ECU 50 displays the upper limit power Pmax calculated in step S32 on the power meter. In step S34, control is returned to the main routine.

FIG. 14 is a diagram showing a display example in which the upper limit power is displayed on the power meter.
In the example shown in FIG. 14, the color of the band-shaped background region along the locus along which the tip of the pointer indicating the output power P moves is configured to be changeable. The background area is displayed so that the color of the portion showing the output power 0 to Pmax is different from the color of the portion showing the output power higher than the upper limit power Pmax. Any display may be used as long as the upper limit power Pmax can be identified as the boundary value, but it is preferable that the color of the portion showing the output power higher than Pmax is displayed lighter than the color of the portion showing the output power 0 to Pmax. Alternatively, the color of the background portion where the output power is 0 to Pmax may be changed to green, and the color of the background portion indicating that the output power is higher than Pmax may be changed to red.

FIG. 14 shows an example in which the analog pointer moves on the background with the dial. However, the digital display of the vehicle speed and the upper limit vehicle speed as shown in FIG. 12 is changed to the digital display of the power and the upper limit power. It may be.

It is preferable that the display device displays the current output power and the boundary value indicating the upper limit power in a manner that can be viewed simultaneously. As a result, the driver can easily travel so as not to exceed the upper limit power by adjusting the degree of depression of the accelerator pedal.

As described above, according to the present embodiment, a display that allows the driver to suppress an increase in vehicle speed or traveling power is displayed, so that a vehicle whose efficiency decreases as the vehicle speed or traveling power increases is driven. It can be expected that the rider can run efficiently, and the possibility of reaching the destination without additional charging is increased.

The calculation of the upper limit vehicle speed and the upper limit power may be determined by setting an appropriate margin in the course of the calculation method described in the present embodiment, or may be calculated by another method.

Further, in the present embodiment, the example in which the boundary value displayed according to the SOC and the distance to the destination is changed has been described, but it is not always necessary to consider the distance to the destination, and the SOC is a predetermined low value. When the level state is reached, the boundary value of the recommended travel area may be lowered to ensure the travelable distance.

The embodiment disclosed this time should be considered as illustrative in all points and not restrictive. The scope of the present invention is defined by the terms of the claims, rather than the description above, and is intended to include any modifications within the scope and meaning equivalent to the terms of the claims.

10 power storage device, 20 inverter, 30 motor generator, 35 drive wheel, 37 wheel speed sensor, 42 voltage sensor, 44 current sensor, 46 temperature sensor, 60 display device, 100 electric vehicle, 110 SOC calculation unit, 120 power consumption detection unit , 130 vehicle speed detection unit, 140 display control unit, 150 storage unit, 160 planned travel distance detection unit.

Claims

An electric vehicle display system,
The electric vehicle is
A power storage device (10);
An electric motor (30) that receives electric power from the power storage device and generates a driving force,
The display system includes:
A display device (60) for displaying vehicle information to the occupant;
A control device (50) for causing the display device to display a boundary value that divides the inside and outside of the recommended travel area set in order to ensure the travel distance of the vehicle according to a parameter related to the distance traveled by the electric vehicle. A display system for an electric vehicle.
The parameter is
Including the distance to the destination of the electric vehicle,
The display system for an electric vehicle according to claim 1, wherein the control device sets the boundary value according to a distance to a destination.
The parameter is
Including the state of charge of the power storage device,
The display system for an electric vehicle according to claim 1, wherein the control device sets the boundary value according to a state of charge of the power storage device.
The parameter is
The state of charge of the power storage device;
A distance to the destination of the electric vehicle,
The electric vehicle display system according to claim 1, wherein the control device sets the boundary value according to a state of charge of the power storage device and a distance to a destination of the electric vehicle.
The recommended travel area is defined for vehicle speed,
The display system for an electric vehicle according to any one of claims 2 to 4, wherein the boundary value indicates an upper limit speed at which the power storage device in the charged state can travel the distance.
6. The display system for an electric vehicle according to claim 5, wherein the display device displays a current vehicle speed and the boundary value in a manner that can be visually recognized simultaneously.
The recommended travel area is defined for power,
The display system for an electric vehicle according to any one of claims 2 to 4, wherein the boundary value indicates an upper limit power that can be output when the power storage device in the charged state travels the distance.
The display system for an electric vehicle according to claim 7, wherein the display device displays the current output power and the boundary value in a manner that can be visually recognized simultaneously.
The control device updates the boundary value based on a change in a state of charge of the power storage device due to traveling and a change in a distance to the destination of the electric vehicle due to traveling, and causes the display device to display the boundary value. Item 5. The display system for an electric vehicle according to any one of Items 2 to 4.
An electric vehicle comprising the display system according to claim 1.