CS219224B1 - Wiring to protect the batteries from being damaged by excessive current - Google Patents

Abstract

The circuit for protecting batteries from destruction by excessive current consists of a fused voltage source connected to a battery charger connected to the fault sensor in series by an isolation circuit, while an error amplifier with a power element connected to the fused voltage source is connected to the fault sensor.

Description

(54) Wiring to protect accumulators from excessive current destruction

The circuitry for protecting the accumulators from destruction by excessive current is constituted by a fused voltage source connected to the battery charger connected to the fault sensor in series by a decoupling circuit, and a fault amplifier with a power member connected to the protected voltage source is connected to the fault sensor.

BACKGROUND OF THE INVENTION 1. Field of the Invention The invention relates to circuitry for protecting accumulators from excessive current destruction.

Accumulators as energy sources, especially for portable electronic devices, are increasingly being used with the development of microelectronics. Their advantage is the possibility of regenerating energy by charging from the grid. Most battery chargers are integrated in the device and operate fully automatically when the device is connected to the mains, and the charging circuits ensure that the charging cycle does not exceed the specified limits. In the event of an accident or failure of the stabilizing circuits, these can be damaged by passing a current of magnitude into the accumulator, which can cause not only the destruction of the expensive accumulator, but the whole device, and the operator usually need not be informed in advance.

The above-mentioned drawbacks are eliminated by the circuit according to the invention, which is characterized in that the error amplifier has a filter capacitor connected by one electrode to zero potential and the other electrode connected to the control electrode of the power member thyristors and coupling. to a collector of a switching transistor having a base connected to a base resistor which is connected to the first output of an optocoupler. and on the one hand through a working resistor of the opto-emitter of the switching transistor, and to a zero potential via a consecutively connected first protective Zener diode and a second protective Zener diode, to the switching transistor emitter and the cathode of the first protective Zener diode the optocoupler input and battery charger and the second optocoupler output are connected to zero potential, the second optocoupler input is connected via the opto-coupler diode working resistor to the amplifier transistor collector, which is connected via the amplifier transistor base resistor to the first fault sensor output and for setting the amplifier transistor operating point and the fourth capacitor at the second output of the fault sensor and at the same time through the second and third filter capacitors to zero potential, the emitter of the amplifier transistor being connected: e faults and through the second and third filter capacitor to zero potential.

The advantage of the circuitry according to the invention lies in particular in eliminating the possibility of a battery accumulator failure, which for example in the case of tight batteries is manifested by mechanical deformation, which results in the destruction of the accumulator and damage to the device. In addition, the wiring protects the battery in the event of improper operation, for example during instrument recovery, or during repairs and measurements, where the charger may also be destroyed. Another advantage is undoubtedly that the wiring is low on the components used and works reliably even in limit modes. The power element which is part of the circuit according to the invention may preferably have a sound signaling or light signaling in the terminal circuit. In addition, a limiting resistor may be connected in series to the thyristors to prevent the maximum current of the power member from being exceeded.

An exemplary canopy embodiment according to the invention is shown in the accompanying drawings, in which Fig. 1 is a block diagram;

is one of the variants of detailed connection.

The circuit according to the invention consists of a fused voltage source 1, which is connected both to the battery charger 2 and to the thyristor 8 of the power element 6, whose control electrode is connected to the error amplifier filter capacitor 9 and to the coupling resistor 10 connected simultaneously to the collector resistance 11. And a zero potential and to a switching transistor 12 having a base connected to a base resistor 13 which is connected both to the first output 21 of the optocoupler 18 and to the emitter of the switching transistor 13 via a working resistor 14 of the optocoupler 18; the first protective Zener diode 15 and the second protective Zener diode 16, each connected to the emitter of the switching transistor 12 and the cathode of the first protective Zener diode 15, are operatively connected. 17 connected to the second input 19 of the optocoupler 18a, to the battery charger 2 and the second output 22 of the optocoupler 18 is connected to zero potential, the second input 20 of the optocoupler 18 is connected via the resistor 23 to the collector of the amplifier: should be connected first, through the resistance of 27-base amplifier, transistor? 26 na. First, it senses 3 faults a. On the one hand through the resistor: 28 _.: to set the operating point of the amplifier? and a fourth filter capacitor. 33 na? second output: fault sensor 3 and at the same time via the second and third filter capacitors 24, 25 to zero potential, the emitter of the amplifier transistor 26 being connected simultaneously to the second output 32 of the fault sensor and through the second and third filter capacitors 24, 25 to zero potential . The battery charger 2 is connected further to the first and second resistors 29, 30 of the fault sensor 3, which is connected to a decoupling circuit 4 in which the first and second diodes 34, 35 are connected in parallel in the forward direction. battery connection.

The circuit works so that if the charging current does not exceed the specified value, the voltage drop across the resistors 29, 30 of the fault sensor is small and cannot open the amplifier transistor 28. Therefore, the collector current does not flow through the first and second optocoupler inputs 19, 20. 18. For this reason, the phototransistor of the optocoupler 18 remains closed and its outputs 21, 2224 do not flow through the collector current. The switching transistor 12 also remains closed, since its base is connected to the emitter potential through the resistor 13 of the switching transistor 12 and the working resistor 14 of the optocoupler 18. There is zero potential on the collector of the switching transistor 12. The thyristor 8 remains closed for these reasons. If, for any reason, the charging current increases above the selected limit, the amplifier transistor 26 opens and the current flows through its collector and thus through the diode of the optocoupler 18. At the same time the phototransistor of the optocoupler 18 opens. In the collector of the switching transistor 12, a voltage occurs which, via the coupling resistor 10, drives the thyristor 8 of the power element 6. The thyristor 8 opens and short-circuits the fused voltage source 1 and the fuse 7 resets. This prevents further overcharging and possible damage or destruction of the battery. The protective Zener diodes 15, 16 together with the working resistor 17 form an overvoltage protection of the optocoupler 18 and the switching transistor 12.

The connection according to the invention should be used wherever it is necessary to ensure trouble-free operation of the accumulator.

Claims (1)

SUBJECT Wiring to protect accumulators from excessive current destruction, consisting of a fused voltage source connected to a battery charger connected to a fault sensor in series with a decoupling circuit, and a fault amplifier with a power member connected to the fused voltage supply is connected to the fault sensor. the amplifier (5) has a filter capacitor (9) connected by one electrode to the zero potential and the other electrode to the control electrode of the thyristors (8) of the power element (6) and to the coupling resistor (10) connected via the collector resistor (11) to zero potential; to a collector of a switching transistor (12) having a base connected to a base resistor (13) connected both to the first output (21) of the optocoupler (18) and to the emitter of the switching transistor (18) 12), and to zero potential via a consecutively connected first protective Zener diode (15) and a second protective Zener diode (16), further to the emitter of the switching transistor (12) and the cathode of the first protective Zener diode (15) is connected a working resistor (17) connected to the first input (19) of the optocoupler (18) and (2) the accumulator and the second output (22) of the optocoupler (18) is connected to zero potential, the second optocoupler input (20) is connected via a working resistor (23) of the optocoupler diode (18) to the collector of the amplifier transistor (26) connected via a base resistor (27) to a first output (31) of the fault sensor (3) and a resistor (28) for setting the amplifier transistor (26) operating point and a fourth filter capacitor (33) to a second output (32) of the sensor (3). 3) faults and at the same time via the second and third filter capacitors (24, 25) to zero potential, the emitter of the amplifying transistor (26) being connected simultaneously to the second output (32) of the fault sensor (3) and through the second and third filter condenses zero potential (24, 25).