JP3421684B2 - Battery display device for electric vehicles - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a battery remaining capacity display device for displaying the remaining capacity of a battery for supplying power to a motor in an electric vehicle driven and driven by a motor. 2. Description of the Related Art In an electric vehicle, it is absolutely necessary to display the remaining capacity of a battery in order to determine the possible travel distance, and various battery remaining capacity display means are used. For example, there is a method of measuring the terminal voltage of a battery and displaying the remaining capacity of the battery. In this method, when the battery terminal voltage fluctuates due to the load state on the motor, the remaining capacity of the battery greatly decreases or increases. And it is incorrect. Another method of displaying the remaining battery capacity is to display the remaining battery capacity by subtracting the consumed power from the fully charged battery capacity. However, there is a method for displaying the remaining power of the motor, the temperature of the battery, the regenerative power, and the time. It is not possible to accurately display the remaining amount, even if it processes a huge amount of information such as exhaustion. Even if it is displayed that there is a capacity, running becomes impossible, and an error from the actual remaining capacity becomes conspicuous. [0003] The present invention seeks to display the remaining capacity of a battery using relatively simple arithmetic means. [0004] In a battery remaining capacity display device for an electric vehicle, the remaining capacity of a battery B mounted on the electric vehicle is displayed by the number of light emission of the light emitting diode 1 according to the remaining capacity. While the terminal voltage V of the battery B is equal to or higher than the predetermined voltage and the discharge amount is lower than the predetermined amount, the light emitting diode 1 emits light with the remaining capacity based on the integration result of the discharge amount.
The number of lights is determined and displayed, and the terminal voltage V of the battery B becomes a predetermined voltage.
Battery B remaining at a pressure less than or equal to or greater than a predetermined amount
When the amount decreases, the display shifts to the remaining capacity display based on the terminal voltage V of the battery B, and based on the terminal voltage V
Indicates that the terminal voltage V has a predetermined voltage range for a predetermined time.
To change and display the number of light emitted by the light emitting diode 1.
It has a structure of the electric vehicle battery residual capacity display device according to claim that. According to the battery remaining capacity display device described above, the terminal voltage V of the battery B is equal to or higher than a predetermined voltage.
When the accumulated discharge amount is less than the predetermined amount and there is sufficient traveling reserve, the number of light emission of the light emitting diode is controlled to indicate the remaining capacity by displaying the integrated result of the discharge amount, so that the battery is controlled. Unlike the control by measuring the terminal voltage of B, the number of light emission of the light emitting diode does not change under the load condition of the motor and is stable. When the remaining capacity of the battery B decreases, the terminal voltage V of the battery B directly changes. Since the number of light emission of the light emitting diodes is controlled, it is possible to relatively accurately predict when the electric vehicle stops running. If the terminal voltage V of the battery B is maintained in a predetermined voltage range for a predetermined period of time to determine the number of light emission of the light emitting diode 1, the number of light emission may be changed when the control is shifted to the control of the number of light emission at the terminal voltage V of the battery B. Can be prevented from flashing when the terminal voltage V increases or decreases. An embodiment of the present invention will now be described with reference to the drawings. The block diagram of FIG. 1 shows the input and output of control signals by the arithmetic and control unit 10 of the electric vehicle. The amount of turning operation of the accelerator lever 11 by the potentiometer, the ON / OFF signal of the travel switch 12 and the low level of the speed change switch 13 are shown. The medium / high speed setting speed is input to the arithmetic and control unit 10 to set the driving conditions. The battery B supplies power to the arithmetic and control unit 10 via the CPU supply power supply circuit 14 and supplies power to the motor 15 via the main relay 16. Also. The terminal voltage V is input to the arithmetic and control unit 10 via the battery voltage detection circuit 17, and the current value flowing through the battery B is input from the battery current detection circuit 18. Charging power is supplied to the battery B via a charging control circuit 20 connected to a power supply 19. The charging control circuit 20 is controlled by the arithmetic and control unit 10 to control the charging power supplied to the battery B. I have. The rotation of the motor 15 is controlled by the arithmetic and control unit 10 via the motor drive circuit 21, the forward / reverse switching circuit 22 and the power generation braking circuit 23. The rotation speed is input from the encoder 26 connected to the motor 15 to the arithmetic and control unit 10 via the rotation speed detection circuit 24, and the electromagnetic brake driving circuit 2
The electromagnetic brake 27 connected to the motor 15 via the motor 5 operates. The remaining capacity indicator 3 is composed of five light-emitting diodes (LEDs) 1 and is configured such that the remaining capacity of the battery B is fully illuminated when it is fully charged, and sequentially disappears as the battery B is discharged. Next, a lighting control state of the light emitting diode 1 of the remaining capacity indicator 3 by the arithmetic and control unit 10 will be described with reference to a flowchart of FIG. 2 as an example of control using a battery B having a 24 V capacity of 35 Ah. In step S1, the terminal voltage V is measured.
Is integrated with the current value I measured in step (1) and the time T. Step S3
Then, it is determined whether the terminal voltage is greater than 23.5V,
In step S4, it is determined whether the discharge amount is less than 50% of the full charge. If the determinations in steps S3 and S4 are "YES", the remaining capacity of the battery is calculated in step S5, the number of lighting N is calculated from the remaining capacity C in step S6, and the light emission of the light emitting diode is displayed on the display 3 in step S7. The remaining capacity is displayed with the number being N. The number of lights N is N = 5 when all five light emitting diodes 1 emit light when fully charged.
It is assumed that N = 4 for turning off one light emitting diode 1 when the remaining amount is 85% or less, and N = 3 for turning off the second light emitting diode 1 when the remaining amount is 70% or less. Next, if the determination in step S3 or S4 is "NO", the battery voltage detection circuit 1
The number of light emission of the light emitting diode 1 is controlled as follows based on the terminal voltage V detected at 7 as a criterion. Step S 18 in the terminal voltage V is determined whether 23.5 volts persisted for 10 seconds at less than 23.75 volts, a 3 lighting exponent n in If YES step S9, step S10
The process proceeds to step 11 if NO. In step S11, when the terminal voltage V is less than 23.5 volts and 2
It is determined whether or not 2.5 volts or more has continued for 10 seconds. If YES, the lighting index n is set to 2 in step S12 and the process proceeds to step 10. If NO, the lighting index n is set to 1 in step S13 and the process proceeds to step 10. I do. In step S10, step S14, and step S15, the lighting number N is not set to be larger than the lighting number N up to the previous time, so that the light emitting diode 1 that has been turned off is not turned on again. Once the process shifts to the remaining capacity determination at the terminal voltage V, even if the terminal voltage V temporarily increases, the discharge amount determination in step S4 does not shift to the determination based on the discharge amount again. Further, only three remaining light emitting diodes 1 are controlled by the terminal voltage V. Even if the terminal voltage temporarily increases, the two fully charged light emitting diodes do not emit light. The light emitting diode 1 of the remaining capacity indicator 3 may increase the number of light emission when the remaining capacity of the battery B decreases, contrary to the above.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a control block diagram of an electric vehicle. FIG. 2 is a flowchart of a remaining capacity control of a battery. [Description of Signs] 1 Light-emitting diode B Battery V terminal voltage

Continuation of the front page (58) Field surveyed (Int.Cl. ⁷ , DB name) B60L 3/00 G01R 31/36 H02J 7/00

Claims (1)

(1) An electric vehicle battery for displaying the remaining capacity of a battery (B) mounted on the electric vehicle by the number of light emitting diodes (1) according to the remaining capacity. In the remaining capacity display device, while the terminal voltage (V) of the battery (B) is equal to or higher than a predetermined voltage and the amount of discharge is less than the predetermined amount, the light emitting diode has a remaining capacity based on the integrated result of the amount of discharge.
The number of light emission of (1) is determined and displayed, and the terminal of the battery (B) is determined.
The voltage (V) is lower than a predetermined voltage or the discharge amount is higher than a predetermined amount
When the remaining capacity of the battery (B) decreases, the battery (B)
To display the remaining capacity based on the terminal voltage (V)
In both cases, the indication based on the terminal voltage (V) is
When the voltage (V) continues for a predetermined time within a predetermined voltage range,
A battery remaining capacity display device for an electric vehicle, wherein the number of light emissions of a photodiode (1) is changed and displayed .