SU1561115A1 - Dc switch - Google Patents

Abstract

The invention relates to switching equipment of direct current, high voltage. The purpose of the invention is to increase the breaking capacity and reduce the weight and size parameters of the switch. Connecting the demagnetizing winding 8 droplets 3 through the key element 11 to the circuit consisting of capacitors 9 and inductors 10, allows to reduce the approach speed of the current in the circuit of the power contact 1 to zero, which increases the breaking capacity . 2 hp ff, 2 ill.

Description

Fig, 1

The invention relates to electrical engineering, in particular, to high voltage switching equipment, and is intended for switching DC current.

The purpose of the invention is to increase the breaking capacity and reduce the weight and size of the switch.

Fig, 1 presents the circuit breaker; Fig. 2 shows an embodiment of the switch.

The switch contains the power contacts 1 and the first winding 2 in series with the ferromagnetic heart h ,, connected in series with it,. In parallel, they are connected to a capacitor 5 with a key element 6, which can be, for example, a controlled arrester. With charging device 7, Drossel 3 also contains a second demagnetization winding 8, which covers the same (core h. Winding 8 is included in a circuit containing capacitors 9E of inductance coil 10 and a key element 11, which may be, for example, a discharge. The capacitors 9 and the inductors have such characteristics and are connected in such a way that the discharge tone of the capacitor has approximately a rectangular shape. The charger 12 is designed to charge the capacitors 9 The switch operates as follows

I

in a way.

After opening the power contact 1, the arc burns on them. After the contacts are disconnected at an arc-suppressing distance, the discharge switch 6 is ignited, which causes the discharge of capacitors 5 through the arc at power contacts 1. The charge of capacitors 5 must be so polar that the direction of its discharge current in the circuit of power contacts 1 in the first ass - the period was the opposite of the current being turned off. Simultaneously, the ignition of the discharger is ignited and through the winding 8 of demagneiooani - the discharge of capacitors. The current of this discharge should be approximately constant for a time longer than a quarter of the period of discharge of the capacitors 5, and its value is close to the core reversal current k. Then, when the current in the circuit of contacts 1 approaches zero, the magnetic flux in the core of the choke 3 also

Q

five

five

approaching zero. In this case, the inductance of the winding 2 increases dramatically, which leads to a corresponding decrease in the rate of current approach to zero in the circuit of the power contacts 1.

Figure 2 shows a variant of the proposed switch, in which the demagnetization current of the core k is generated by the discharge of the capacitor 9 through the resistor 13. The constant time of this discharge must be on the order of or more than a quarter of the period of the discharge of the capacitor 5. The discharge of the capacitor 9 is carried out Using the same discharge coil 6 as the discharge of capacitors 5, this circuit also has one charging device 7, common to capacitors 5 and 9. In order for the discharge of these capacitors to be independent of each other, between their circuits delivered for projectile loader resistor I.

The use of a second winding in an inductance coil with a ferromagnetic core, which is used to create demagnetization of this core when the current approaches zero, reduces the current approach speed in the arc-suppressing device to zero hundreds of times. Calculations show that this reduces the capacitance of capacitors by a factor of 2-3 when the limiting currents are switched off.

Claims (3)

1. A switch of direct current, containing a terminal for connecting a power source and a terminal for connecting a load, power contacts, the main winding of the throttle, located on the ferromagnetic core, the main capacitor and the main key element, at least one circuit consisting of serially connected previously the charged capacitor and the limiting element, and the charge unit of the main capacitor, and the output for connecting the power source is; The main winding of the throttle, the power contacts and the output for connecting the load are connected in series, the main capacitor and the main key element are connected in series and connected in parallel to a section of this circuit from the series-connected main winding of the throttle and power contacts so that the polarity of the preliminary charge of the bases 156 A capacitor of opposite polarity is the voltage of the power source, which, in order to increase the breaking capacity and reduce the weight and size of the circuit breaker, an additional winding of the harness is inserted into it, we accept the terminals of the winding of the harness. connected additional capacitor and limiting element so that the additional winding of the throttles is demagnetizing with respect to the main winding of the throttles. 2. A switch according to any one of the following: an inductor is used as a limiting element, an additional key element is used as a key element, and these circuits containing limiting elements and additional capacitors connected in parallel. 3. A switch as distinguished in that, in order to allow the charge of an additional capacitor from the charge block of the main capacitor, a charge resistor is introduced into it, a resistor is used as a limiting element, and a circuit consisting of series-connected limiting element and an additional the capacitor is connected in series with the additional winding of the throttles and is connected in parallel to the main key element, one output of the charging resistor is connected to the output for connecting the load ki, another lead of the charged resistor is connected to the circuit between the auxiliary capacitor and the additional winding of the choke switches. and FIG. 2