JPS6312981A - Internal resistance measuring device for battery loaded on car - Google Patents

Abstract

PURPOSE:To measure an internal resistance of a battery while loading on a car and to prevent annihilation of a data by measuring a voltage and current of the battery used for loading on the car and of an electric load and computing the internal resistance of the battery. CONSTITUTION:The resistances of the electric load 1, 2 are denoted by R1, R2, the internal resistance of the battery is denoted by R3 and electromotive force is denoted by e. First, when only a switch ACC turns on, E=E1+R3I1 is obtained from E=(R2+R3)I1 where, I is the current which flows from the battery 7 to the load 2, E1 is the terminal voltage of the battery 7. Next, when a switch IG 6 turns on, E=E2+R3I2 is obtained from E=(R11/R2+R3)I2 where, I2 is the current which flows from the battery 7 to the load 1, 2, E2 is the terminal voltage of the battery 7. From above both equations, E1+R3I1=E2+R3I2 therefore R3=(E1-E2)/(I2-I1) is obtained. The current I1, I2 are measured by a current sensor 3, the voltage E1, E2 are measured by an operation part 4, then the operation part 4 calculates and display 5 the internal resistance R3 of the battery 7 using this measured value, the service life of the battery 7 is thereby estimated.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a vehicle-mounted storage battery internal resistance measuring device that measures the internal resistance of a vehicle-mounted storage battery and estimates the life of the storage battery.

[Conventional technology]

Conventionally, the internal resistance of a storage battery has been measured to estimate its lifespan, but in order to measure the internal resistance of a storage battery, the storage battery must be disconnected from the car's circuit, and the storage battery must be connected to an external load and It was necessary to connect a voltmeter and ammeter.

[Problem that the invention seeks to solve]

As mentioned above, in the past, when measuring the internal resistance of a car storage battery, it was necessary to disconnect the M battery from the car's onboard circuit, which resulted in the problem that all the data that should always be kept in memory, such as a clock or an electronically tuned radio, would be erased. There was a point. In addition, it was necessary to connect an external load, a voltmeter, and an ammeter to the separated storage battery, making the work extremely troublesome.

This invention was made to solve the above-mentioned problems, and it is possible to measure the internal resistance of a storage battery while it is attached to a vehicle, prevent data from disappearing, and improve the connection of storage batteries, etc. The purpose of the present invention is to obtain an in-vehicle storage battery internal resistance measuring device that does not require separation.

[Means for solving problems]

The on-vehicle storage battery internal resistance measuring instrument according to the present invention is provided with a measuring means for measuring the voltage and current of an on-vehicle storage battery and an on-vehicle electric load, and a calculating means for calculating the internal resistance of the storage battery from the measured values of the measuring means. It is.

[For production]

In this invention, the voltage and current of an on-vehicle storage battery and an electric load are measured, and the internal resistance of the storage battery is calculated from the measured values.

〔Example〕

Embodiments of the present invention will now be described with reference to the drawings. 1st
In the figure, reference numeral 1 denotes an electrical load having a resistance value R, which is energized when the IG switch 6 is turned on. 2 is an electric load with a resistance value R2 that is energized when an ACC switch (not shown) is turned on; 3 is a current detection sensor; 4 is a storage battery 7 from voltage and current;
5 is a display section that shows the calculation result. The storage battery 7 has an internal resistance R3 and an electromotive force E.

Next, the operation of the above configuration will be explained. First, when only the ACC switch is on before the ■G switch 6 is turned on, let the current flowing from the storage battery 7 to the electrical load 2 be ■1, and the terminal voltage of the storage battery 7 be E, then E= (R, +R3) I, to E = E, +
R313 (1) Next, if the current flowing from the storage battery 7 to the electrical loads 1 and 2 when the IG switch 6 is turned on is 2, and the terminal voltage of the storage battery 7 is E2, then E= (R, /R2+R3) 12 to E =E2+R3
12+21 From the above (1), +21 formula, E, +R311 = E, +R31° Therefore, R, = (E, E2 > / (Ia K
' becomes.

Above-mentioned current 1. , I, are measured by the current detection sensor 3, terminal voltages E, , E, are measured by the calculation unit 4,
From these measured values, the calculation unit 4 calculates the internal resistance R3 of the storage battery 7.
is calculated and displayed on the display section 5. Therefore, the lifespan of the storage battery 7 can be estimated from the display on the display unit 5. Note that the display section 5 can be used as an ammeter, a voltmeter, or a wattmeter.

〔Effect of the invention〕

As described above, according to the present invention, the voltage and current of the in-vehicle storage battery and the in-vehicle electrical load are measured, and the internal resistance of the storage battery is calculated. can be detected, and the lifespan of the capacitor can be easily estimated without data loss.

[Brief explanation of the drawing]

FIG. 1 is a block diagram of an apparatus according to the invention. 1ν2°°° electrical load, 3... current detection sensor, 4.
...Arithmetic unit, 5...Display part, 6...IG switch,
7...Storage battery.

Claims (1)

[Claims] (1) In-vehicle storage battery internal resistance measurement characterized by comprising a measuring means for measuring the voltage and current of an in-vehicle storage battery and an in-vehicle electrical load, and a calculation means for calculating the internal resistance of the storage battery from the measured values of the measuring means. vessel.