SU1568117A1 - Method of measuring short circuit resistance of chemical current source - Google Patents

Description

The invention relates to electrical engineering, in particular to chemical

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current sources (HIT). The purpose of the invention is to improve the accuracy of measurement of short circuit resistance.

To determine the short circuit resistance, they measure the emf of the HIT, the capacitor load is precharged from the voltage source of reverse polarity, the HIT is discharged to the capacitor load and during the discharge at the time when the voltage at the HIT terminals is zero, the discharge current is measured, and then the short-circuit resistance is calculated . 2 Il.

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The invention relates to electro. technology, in particular to chemical current sources, and can be applied when determining the parameters of batteries and batteries.

The aim of the invention is to improve the accuracy of measurements.

Figure 1 shows the electrical circuit for measuring the short circuit resistance of the HIT according to the proposed method; Fig.2 shows the dependence of the voltage on the HIT and the discharge current on time.

The circuit contains HIT 1 connected in parallel with HIT via switching element 2 and current sensor 3 capacitor 4 connected, through the second switching element 5, voltage source 6 of reverse polarity, connected in parallel with HIT 1 voltage sensor 7, the output of which is connected to the first threshold input

device 8. The second input of the threshold device is connected to the reference voltage source (and _op ), ^{and the} output to the synchronization input. (eap5 ^g ck sweep) electronic storage oscilloscope 9. Input of the oscilloscope 9 is connected to the output of the sensor 3. In addition, the circuit contains a voltmeter 10 connected in parallel with HIT 1.

The method of measuring the short circuit resistance HIT is as follows.

Measure the emf of the HIT, then connect the capacitor 4 with the help of the second switching element 5 to the source 6 voltage of reverse polarity and charge the capacitor 4. After charging the capacitor 4 it is disconnected by the second switching element 5 from the source 6 of the voltage of reverse polarity and using a commutator., 1568117 A1

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From the moment of time C, (FIG. 2), the recharging of the capacitor 4 begins. The voltage from the voltage sensor 7 and 3 current flows to the first input of the threshold device .8 and to the input ограф of the oscilloscope 9, respectively. When voltage is on. sensor output ·? voltage will correspond to the voltage on HIT 1 (equal to zero), which means a short circuit of the HIT when compensating for the voltage drop in the connecting wires and on the resistances of the switching element 2 of the current sensor 3 by the reverse voltage of the capacitor 4, the threshold device 8 triggers and outputs a signal to start the sweep 9, on the screen of which a curve of the change of the discharge current is recorded, starting from the moment of time. Since the change in resistance of the switching element 2 when it is turned on, occurs on the segment Strap - it does not affect the result of the discharge current measurement.

Calculating the ratio of the emf of the HIT to the maximum value of the discharge current (short circuit current) at time P ₄ , determine the resistance of the short circuit of the HIT.

Proposed method for measuring short circuit resistance

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HIT compared to the prototype will improve the measurement accuracy by eliminating the influence of the resistance of the switching element when it is turned on the measurement result, compensating for the voltage drop on the connecting wires and the resistance of the switching element in the measurement process, exceptions when calculating the short-circuit resistance of the capacitor having a technological variation.

Claims (1)

Claim A method for measuring the resistance of a short circuit of a chemical current source (HIT) by measuring the voltage at the source, discharging it to a capacitor load, and determining the desired resistance by calculation, characterized in that, in order to improve measurement accuracy, the EMF HIT is measured, the load is pre-charged from an additional source polarity opposite to the HIT and during the discharge of the HIT at the time when the voltage at the HIT terminals is zero, the discharge current is measured and the resistance is determined shortly of the circuit by dividing the electromotive force by the value measured discharge current. FIG. one 1568117