SU454538A1 - Variable voltage step change device - Google Patents

Description

one

The invention can be applied in electrical engineering for cases of discrete voltage control without breaking the consumer's power supply circuit, for example, in installations for testing the electrical insulation of electrical circuits. In addition, it can be used in AC voltage stabilizers, including for powering household electrical installations.

Step alternating voltage devices are known that contain a supply transformer, switches and a control unit.

However, when switching from one voltage level to another, the switching element controls the total power consumed by the load, and at the moment of switching the load is disconnected from the voltage source.

The purpose of the invention is to facilitate the operation of the switch with discrete control of the voltage across the load and the elimination of voltage breaks during switching.

To do this, in the proposed device, the secondary winding of the transformer is placed on the main core of its magnetic core, and on the side cores of the magnetic core, the magnetic circuit of each of which is closed through the main core, are the primary windings, each of which

connected to one bus of the input voltage source, and its end through its switch, connected to the control unit, to another thickness of the source. To reduce the mutual influence between the primary windings, their magnetic cores are separated by non-magnetic spacers.

FIG. 1 shows the electrical circuit of the proposed device; in fig. 2 - shows a transformer.

It consists of a transformer 1, containing the main core 2 of the magnetic core, the magnetic core 3 of the primary windings, non-magnetic gaskets 4, the primary winding 5,

secondary winding 6. Primary windings 5 through switching elements 7 are connected to control unit 8.

When one of the primary windings 5 is connected to a variable voltage source

t / Bx through the switching element 7 in the secondary winding 6 is induced e. d. When the second primary winding is connected in parallel with the first one in the main magnetic circuit, the instantaneous values of the magnetic fluxes add up, respectively. d. in the secondary winding. When connecting the next winding e. d. in the secondary winding increases by one more step. When the next primary winding is connected or disconnected, the voltage in the secondary winding changes by a step without a break for the duration of the switching process.

When switching, the switching element does not commute the entire power of the consumer, but only its increment, which contributes to unloading the switches and facilitating their operation.

Non-magnetic insulation strips 4 eliminate the mutual influence of the magnetic cores of the primary windings, and also prevent the development of eddy currents. The control unit 8 sets the switching program of the switching elements 7.

Subject invention

Claims (2)

1. A device for changing alternating voltage step-by-step, containing a supply transformer, switches and a control unit, characterized in that, in order to avoid a voltage break on the load when switching and to facilitate the operation of the switches, the secondary winding of the transformer is placed on the main core of its magnetic circuit , and on the side rods of the magnetic circuit, the magnetic circuit of each of which is closed through the main rod, the primary windings are located, each of which is connected by its origin with a single winding of the input voltage source, and the end through its switch connected to the control unit with a different input voltage source. 2. A device according to claim 1, characterized in that, in order to reduce the mutual influence between the primary windings, their magnetic cores are separated by non-magnetic spacers.