SU514384A1 - Method for determining the degree of charge of a battery - Google Patents

Description

one

This invention relates to the monitoring of battery capacity under operating conditions.

The known method of controlling the degree of charge of a battery by measuring its electrical parameter, depending on the degree of charge of the battery, and then comparing this parameter with the experimental graph plotted for this type of battery, has a small measurement accuracy, as when determining the desired value only one variable parameter is used.

To improve the measurement accuracy of the proposed method, an alternating voltage of an adjustable frequency is supplied to the accumulator battery, its amplitude-frequency characteristic is measured at 0m and the magnitude of the battery voltage is determined by varying the battery’s voltage and frequency dependencies by varying the frequency and voltage battery capacity.

FIG. 1 is a schematic diagram of the device implementing the proposed method; FIG. 2 - amplitude-frequency characteristics of the battery type KNB-60, obtained using this

devices; in fig. 3 - AC voltage drop across the battery KNB-60 depending on its capacity for the three selected frequencies.

The device consists of a generator of adjustable frequency 1, the voltage from the output of which is fed through a coupling capacitor 2 n to a resistor 3 to a battery (4).

A voltmeter 5 and a frequency meter 6 measure the unyielding voltage of the battery 4 and the frequency of the generator 1.

It is known that the battery's complex AC resistance for an alternating current has an inductive and capacitive component.

The method is based on the fact that the capacitive and inductive resistance of a battery varies depending on the state of battery.

The curves shown in FIG. 2. removed as follows.

It reads the voltmeter 5 when the frequency of the generator 1 changes from 20 Hz to 10 kHz for a charged battery and after outputting the capacitance (discharge) to 6, 15, 45, 55 A / h. According to the results of measuring devices 5 and 6, amplitude-frequency characteristics were constructed (Fig. 2) in the laboratory of the 1st

on the degree of discharge (capacity) of the battery.

By curves (Fig. 2), three fixed frequencies of 20, 100, and 800 Hz were selected for example, and the dependences of the voltage drop of a sinusoidal current U on the battery 4 were plotted depending on its capacity in ampere hours for these frequencies (Fig. 3) .

The current value of the battery capacity is determined in the following sequence.

The frequency meter 6 sets the frequency of the generator 1, for example 20 Hz, and the reading of the voltmeter 5, the curve 1 of FIG. 3 counts battery capacity. Similarly, the capacitance is read at other selected frequencies of 100 and 800 Hz and an arithmetic average value is calculated.

F o rm a invention

The method of determining the degree of charge of a battery by measuring its electrical parameter, depending on the degree of charge of the battery, and then comparing this parameter with an experimental graph plotted for this type of battery, distinguishes and with the tag that increase the accuracy, a variable voltage alternating voltage is applied to a battery, its amplitude-frequency characteristic is measured, and the degree of charge and battery are measured by the magnitude of the frequency and voltage on the basis of experimental curves prebuilt iapr voltage and frequency by varying the capacitance of the secondary battery.