SU917228A1 - Device for arcless switching of direct current - Google Patents

Description

(5t) DEVICE FOR ELECTRIC CURRENT ELECTRIC CURRENT

I

The invention relates to electrical engineering, in particular to electrical apparatus.

Devices are known for the arc-free switching of DC and AC 21 current circuits containing a contact and a thyristor unit shunting this contact.

These devices are characterized in that the switching of the current from the contacts to the thyristor block is accomplished by the voltage drop across the arc when the contact is opened. This leads to a burnout of contacts.

The closest to the technical essence of the invention is a contact-valve device for arc-free shutdown of a direct current power circuit, containing a choke connected in series with a contact, shunting their circuit, capacitor and key element, which are connected in parallel to the choke and pin 3.

In this device, the current from the contact to the shunt circuit is switched by using saturation throttles with a reversal circuit (capacitor and key element) to create a small current in the contact circuit just before the contact opens. In this case, due to the fact that the capacitor and the key element shunt the contact circuit and the throttle, the voltage of the capacitor is constantly applied to the contacts, which does not satisfy the requirements of safety precautions.

The purpose of the invention is to improve safety.

Claims (3)

This goal is achieved by the fact that in a device for arc-free switching of electric current, containing a choke connected in series with a contact, shunting their circuit, capacitor and key element, the choke is provided with an additional winding insulated for full voltage from the contact circuit. capacitor through a semiconductor key element. In AC switches and in unpolarized DC switches, the choke is equipped with another additional winding and the other with a semiconductor key element, the connection point of the additional windings is connected to the first capacitor plate, the second plate of which is connected to the anodes of the first and etofx ro semiconductor key The elements of the cathodes of semiconductor grids are connected, respectively, to the other ends of the remote windings. FIG. t is a schematic diagram of a device for direct current coupling; in fig. 2 the same for alternating current commutation. The device contains a choke 1, connected in series with the contact 2, shunt their chain 3, the additional winding which is connected to the precharged capacitor 5 via the semiconductor key element 6, the device (Fig. V) works in the following manner. When the device is switched on, contact 2 closes and current flows through contact 2 and choke 1. After the switching off command triggers, key element 6 is switched on and capacitor 5 is recharged through an additional winding k. Under the action of the current flowing through the additional winding, choke 1 is reversal with. When reverse reversal of the throttles by the main circuit current on pin 2, a small current pause occurs, during which contact 2 is opened and the current into the shunt circuit 3 is switched. If alternating current is switched, key element 7 or 8 of FIG. 2), and the choke is re-magnetized by the action of an eye that flows through an additional winding 9 or 10. Since capacitor 5 is isolated from pin 2, in the open position of the device, pin 2 is not subjected to the voltage of capacitor 5, which increases the safety technique. The proposed device can be used in DC and AC switches. Since the capacitor 5 is connected to the choke 1 through additional windings 4, 9 and 10, it is possible to use low-voltage capacitors, as well as reduce their size and weight. Claim 1. Device for arcuate-free switching of electric current, containing a choke connected in series with a contact, shunt THEIR circuit, a capacitor and a key element, characterized in that, in order to improve safety, the choke is provided with an additional winding insulated for the full voltage from The circuits are connected to the precharged condensate through a semiconductor. nick key element. 2. The device according to claim 1, wherein the choke is provided with an elastic additional winding and another semiconductor key element, the connection point of the additional windings is connected to the first capacitor plate, the second plate, which is connected to the anodes the first and second semiconductor key elements, the cathodes of the semiconductor key elements are connected respectively to the other ends of the additional “1” windings. .. Sources of information taken into account in the examination 1. The author's certificate of the USSR If SSOes, cl. H 01 H 9/30, 1977. 2. Japanese Patent N 50-26013, cl. H 01 H 9/5, 1975. 3. Greenberg L.Ya., Kussul A.M., Ph.D. tech. Sciences Pupynin V.N. The arcless disconnection of the power circuit of the current by the contact-valve device. Electrical industry. Ser. High-voltage devices, transformers, power capacitors. Issue 11 (103), 1979 (prototype).