SU470047A1 - Rectifier device - Google Patents

Description

output parallel (as in Fig. 1) or sequentially. In the particular case of this may be three-phase valve bridges. In this case, the phase of the device will be equal. The beginnings of the secondary windings of the phase-shifting transformer are connected to the clamping power supply of rectifier 4, and the ends to the power supply terminals of rectifier 5. The middle point of each secondary winding is connected to one of the phases of the supply network A, B, C, and each primary winding is connected between the other two phases. It is also possible to connect the primary windings to a star. In the circuit of the primary windings, balancing elements (FIG. 2) may be included in the form of, for example, resistors and chokes 9 to 11. It is also possible to perform symmetry by selecting the parameters of the primary windings. Other phase shifters may be used. In the device described, the phase voltages of the supply network are added to the voltages of the respective secondary half windings of the phase-shifting transformer. The ratio of the amplitudes of the folding nalr 180

sin

and fazheni close to the value

sin 9011- - t

The reference shifts between them are ± 90 °.

As a result, two three-phase voltage systems A B C C and A, B, C are formed.

360 °

With a mutual angular displacement equal to

t

which enter the inputs of the rectifiers 4, and 5. Due to this, a w-phase rectifier mode is provided. Since reactive currents with opposite phases (capacitive and inductive) flow in the secondary windings half-windings, as shown above, in the primary windings, the corresponding reactive components cancel each other out. The resulting reactive TO.K is close to iK zero and the windings flow almost exclusively around the active current. Due to this, the power of these windings and the overall power of the transformer (s) as a whole, as well as other positive results, are significantly reduced.

the effects noted above. At the same time, in order to realize the maximum effect, it is advisable for the secondary windings to perform the windings symmetrically with respect to the primary winding.

The total gain in the total overall power of phase-shifting transformers compared with the known device 2

time. At t 12, the sum is

180 °

I + sin t

Example, the proposed device allows to reduce the installed power of phase-shifting transformers by 1.6 times. The total current to the primary windings of phase-shifting transformers due to their unloading from

180 ° reactive currents reduced in cosec

"

time.

An additional improvement of the proposed device consists in the introduction of 12N-14 contact or contactless switches in its circuit (Fig. 2), which allow, without the use of intermediate transformers, to reduce the need for its output voltage to 180 ° C (i.e.

t 4-8 times at t 12-24)

This reduction, carried out by unlocking the keys 12-14 (with the phase

t. straightening becomes equal), often

It is necessary in generators with low power modes.

Subject invention

An rectifier device containing two rectifiers connected in parallel to the output and connected to the supply network through a phase-shifting transformer, characterized in that, in order to reduce the weight and increase the device efficiency, the input of one of the rectifiers is connected to the beginning, and the other to the end of the secondary windings of a single transformer, the midpoints of which are connected to the phases of the supply network.