SU542294A1 - Battery Charger - Google Patents

Description

one

This invention relates to devices for charging batteries and powering the control circuits of a subway car.

A device for charging a battery with a pulsating current is known, using a key element that limits the choke in the charge circuit, shunted together with the battery by a diode, and a 1J charge control system.

A similar device for charging a battery is also known, using a transistor key element in the f2j charge circuit.

However, these devices are not very reliable and cannot be used to charge the battery of a subway car.

It is also known a device for charging a battery from a direct current network through a thyristor switch with a switching K U - circuit.

The control of this key uses a measuring bridge and a control circuit made in the form of a transistor blocking generator 3j. But this device

has a large number of elements, which is reflected in its energy performance and reliability.

The purpose of the invention is to increase reliability and improve energy performance.

Dp of this device is equipped with a chain of series-connected Zener diode and resistor connected between the minus of the power source and the junction point of the capacitor and the choke of the commutating circuit, the junction point of the Zener diode and the resistor of this circuit is connected through a diode to the base of the blocking transistor generator, parallel connected variable resistor and collector-emitter junction of an additional transistor, the base of which through a diode is connected to the collector of the second additional tional transistor included in the diagonal of the measuring bridge.

The drawing shows the scheme of the proposed device.

Claims (1)

The device contains a thyristor switch 1 with a switching circuit in the form of an oscillating circuit with a switching capacitor 2 and a limiting choke 3. The measuring device of the device is made in the form of a nonlinear bridge on resistors 4–7 and the galbilitron 8, the diagonal of which is connected to a transistor 9. The thyristor controller the key is imputable with a C-blocking generator, consisting of an-anistor 10, a diode 11, a transformer 12, a capacitor 13 and resistors 14.15. It is powered by a blocking generator from Zener diode 16 with a smoothing capacitor 17. A chain consisting of Zener diode 18 of resistor 4-9 and diode 20 monitors the level of voltage on the switching capacitor and serves to prohibit the generation of control pulses before the end of the cycle of its recharging Yes, excluding the possibility of a thyristor key. While thyristor 1 is closed and capacitor 2 does not recharge, the potential of the junction point of capacitor 2 and droplet 3 is greater than the voltage for stabilizing Zener 18, the voltage removed from Zener 18 through diode 20 closes the transistor 10. After recharging capacitor 2, the potential higher than the point drops to zero and the ban is lifted. The battery of the torus battery is connected to the key through the limiting choke 21 and the fuse 22 and is shunted along with the last diode 23. The protection unit against emergency voltage increases is separated from the inductance 24 of the Thyristor 25 and the guide circuit 26. The required input-output characteristic is provided with adjustable resistors 5 , 6 and the transistor 27, which turns the resistor 6 on or off from the nonlinear bridge, changes the ratio of its arms. A battery charging device works in accordance with the following. When the contact network voltage is applied, two cases are possible in principle: the voltage on the battery is greater than U pickup, in this case, for the reasons specified below, the thyristor switch does not work, the charging current is zero and the load on the battery is less than U pickup, the battery starts to charge. The key works with constant pulse duration and frequency, since with the appropriate setting of resistor 5 transistor 9 is closed, transistor 27 is open and the blocking generator generates a constant frequency of the pulse into the thyristor control circuit 1. Charge current is limited with a steel core, which, due to the stored energy during the on state of the thyristor, generates a current in the battery through diode 23 at the time when the key is closed. As the battery is charged, the voltage across it grows and reaches the value and triggered, transistor 9 opens, as the potential of its base becomes more negative than its emitter. Opening the transistor 9 causes the transistor 27 to close and the resistor 6 is turned on in a nonlinear bridge, to close the transistor 10, and therefore to stop the generation of control pulses by the blocking generator. The key stops working, the charge current becomes zero, and the battery begins to discharge to the load. When the battery is discharged to a level equal to or lower than U release, transistor 9 closes, as its base potential becomes more positive than the emitter. The closing of the transistor 9 causes the opening of the transistors 27. 10 and the generation of control pulses by the blocking generator. The thyristor key is started, and the battery starts charging again. Further, the processes are repeated. The circuit provides protection against accidental increases in voltage on the battery. For this purpose, choke 24, thyristor 25 and control circuit 26 serve. For an emergency voltage boost, control circuit 26 generates current in the control circuit of thyristor 25, causing it to turn on and the fuse 22 to burn, the battery disconnects from the mains, and the control circuit remains short-circuited. In this case, two cases are possible: 1. When an overvoltage is caused by the failure of the thyristor 1, a short-circuit protection device installed on the car 2 is triggered. the thyristor is turned off and is no longer turned on. The limitation of the rate of increase of the short circuit current through the thyristor 25 is achieved by the inclusion of throttles 24, the invention The device for charging a battery containing a constant source