SU961075A1 - Dc to ac voltage converter - Google Patents

Description

The invention relates to electrical engineering and may be used to rectify alternating voltages.

Electromagnetic devices based on magnetically controlled sealed contacts — reed switches are known.

In these devices, the reed switch is installed directly on the busbar and the magnet field, formed by the flowing current, crosses the magnetic system of the reed switch, causing, with a certain induction, its operation.

The closest to the present invention is an electromagnetic rectifier of alternating current containing a glass capsule with empty contacts of the corresponding number, in the airless space of which iron filings are placed, which close the corresponding contacts when moving sawdust under the influence of external electromagnetic fields excited in correspondingly located solenoids rectified current from a constant current source 2.

A disadvantage of the known device is its low reliability and efficiency due to the great source of constant

current in the form of batteries and ferropowder, closing the contacts.

The aim of the invention is to increase reliability and efficiency.

The goal is achieved by the fact that the AC voltage to DC converter containing a cylinder with magnetically controlled sealed contacts, an alternating current winding and a source of a constant magnetic field, when performed according to a two-half-wave rectifier circuit with an average output, is provided with a transformer core and an additional cylinder with magnetically controlled sealed contacts, both cylinders located on opposite outer sides of the transformer core and covered

20 electrically conductive screens with permanent magnets on their outer sides.

FIG. Figure 1 shows the structure of a device that implements a two-period loop rectifier input voltage; in fig. 2 shows a variant of controlling the operation of the device of FIG. one.

The converter (Fig. 1) contains core 1, primary winding

2, the secondary winding with a middle terminal consisting of two sections 3 and 4.

On one side of the core 1 there is a cylinder with magnetically controlled sealed contacts 5, which, together with this side of the core, is enclosed by an electrically conductive short-circuited screen 6.; On the opposite side of the core 1 there is another balloon; With the magnetically controlled sealed contacts 5, which, together with this side of the core, is also covered by an electrically conductive short-circuited screen b.

Permanent magnets 7 are placed on the outer side of screens b, placed in non-magnetic sleeves 8, connected to brackets 9 attached to core 1. Permanent magnets 7 are connected to non-magnetic rods 10.- The secondary terminal of the secondary winding is connected to one load terminal eleven.

FIG. Figure 2 shows the variant in which permanent magnets (shown in the example of one of them) are located on the axis of rotation. Thus, the magnet 7 can be rigidly placed on the axis 12. Under the action of a variable input voltage Ug, the primary winding creates a magnetic flux, which is shown by a solid thin line. This magnetic flux induces emf and currents in short-circuited screens. B. The same magnetic flux induces an emf in sections 3 and 4 of the secondary winding.

Under the action of currents flowing through the screens b, secondary magnetic fluxes arise, creating in the zone of the contacts 1 of the control induction B.

At the same time, in the area of contacts 5, there is a magnetic field from permanent magnets 7 with B-- inductions.

In one of the half-cycles of the input voltage (the total induction in the zone of some magnetically controlled sealed contacts is less than the total induction in the zone of other magnetically controlled sealed contacts. This leads to the fact that some contacts are closed and the other are open. In the next half-period of the input voltage, they are closed those contacts, the cat (the first ones were open in the previous half-period. Under the influence of a different picture of the directions of the inductions By and Bm.

With an appropriate selection of magnetomotive forces of magnets and electrical parameters of screens 6, it is possible to achieve that each magnetically controlled sealed contacts 5 will be closed in time strictly equal to the half-period of the input voltage. Thus, the load will have a voltage form corresponding to the full-wave rectifier mode.

The capabilities of the proposed device are expanded, if changing. the position of the magnets 7. By displacing them with the help of the rods 10, you can change the magnitude of the induction in in the zone of magnetically controlled sealed contacts 5. This allows you to change the time of the closed state of the contacts 5. A similar effect can be achieved if the magnets 7 rotate a certain angle relative to the original position (figure 2).

Consequently, another advantage of the converter is revealed: comparative ease of control of its operation.

Thus, the converter is reliable in operation, has an increased efficiency and controllability.

Claims (1)

1. Semiconductor rectifiers. Ed. F.I. Kovalev. M., Energie, 1978, p. 350-352. 2, Patent of the USSR 5563, cl. H 02 M 7/32, 1925. H / j-r..y..fl  m 4J8JL-jD I  I4w 1llll tyx / x / wv ± "./