SU115476A1 - Control method of rectifier-inverter unit with controlled ion valves and transformer - Google Patents

Description

As is well known, in units with ion controlled valves, it is necessary to increase the voltage removed from the secondary winding of the transformer in order to switch from rectifying mode of operation to inverter mode. For this purpose, transformers designed to work with such units use a secondary winding with partitioned leads.

However, copper windings are poorly used in such transformers. So, for example, if you perform the secondary winding of a transformer based on the inverter mode, then in the rectifying mode 20-30% of it will not be used at all. In the inverter mode, the built-in cross section of the copper winding will also be excessively large due to the fact that the mercury valves with grid regulation require a reduction in load compared to the natural ignition of the anodes.

To eliminate this drawback, it is proposed to switch the sections of the secondary winding of the transformer so that, in the rectifying mode, the triangle is composed of full phase windings, and in the inverter mode, of their sections. Not connected to the valves.

The drawing shows a schematic diagram of the proposed unit.

Switching the unit from one mode to another is performed using two three-pole oil switches, shown in the diagram conventionally in the form of contacts 1 and 2. During the rectifying mode, the switch with contacts 1 is closed, as a result of which the secondary winding of the transformer is connected in a "triangle" full phase windings AH, WU and CZ. In the inverter mode, a switch with contacts 2 is closed; the sections AX, WU and CZ of the secondary winding of the transformer are connected in a triangle with external branches AA, BB and CC, to which valves 3 are connected.

If the intermediate terminals A, B and C are made in the middle of the phase windings of the transformer, then at the indicated voltage switching, the valves during the transition to the inverter mode increase by 32% compared to the rectifier mode. If the terminals A, B and C are shifted so that the sides of a small triangle are two times larger than the outer ones. the voltage rise in the inverter mode is 20%.

Switching pins 4 and 5 in the DC circuit is carried out in the usual way.

Subject invention

The control method is an inverter-inverter unit with controllable ionic valves and with a transformer, which is a partitioned secondary winding, made according to the "triangle" scheme, characterized in that, in order to increase the use of transformer copper, in the "triangle" rectifier mode, phase windings of the transformer, and in the inverter one of their sections not connected to the valves.