SU615469A2 - Controllable three-phase inductive-resistive converter - Google Patents

Description

The invention relates to the field of electrical engineering and is an improvement of the BASIC} author. St. No. 416682, in which a phphasic adjustable is proposed: anduct-impacted: a transformer containing a three-phase -path generator with a rotating magnetic field, the beginnings of the primary circuits of which are connected to the supply mains, a three-phase outlet is connected to the ends of the secondary circuits; each phase is connected according to and to the points of their connection a three-phase group of capacitor batteries is connected, the ratio of the reactance of each phase of which to the reactive | Og resistance to the primary winding of the transformer is 3/2.

The disadvantage of this converter is a change in the phase shift between the output current and the supply voltage when the angle of the turn changes between the primary and secondary windings.

In order to eliminate this deficiency, the converter is equipped with an additional three-phase transformer with a rotating magnetic field, the primary and secondary windings of which are connected consistently and a three-phase capacitor group is connected to their connection points, the ratio of the reactive energy of each phase of which to the reactive resistance of the primary windings is equal to 3/2 , the primary windings are connected to the mains, the primary windings are connected to the conclusions of the secondary windings in the additional transformers Transformers, secondary like windings of the coils are connected in parallel, with the axes, the main and additional rotors of the transformers being connected to the shaft, for example mechanical or electric, providing synchronous rotation of the rotors in opposite directions.

Fig. I is a schematic diagram of the converter; in fig. 2 - 6 3 - vector diagram; fig fig. The generator contains transformers with vrashayusch; with magnetic field Tr2, capacitor banks and CI capacitance. With the calsda phase of which is selected (under the conditions of the resistor: (sul - where ii is the inductance of the transformer primary windings; oi is the angular frequency of the source K) the primary windings of the TpjH Tr transformer transformers, the secondary windings of which are connected to counter-parallel, and the three-phase load are connected to the point of their connection, to the terminals of the secondary windings of the transformers T and Tr aP. turns the current vector by 180 e-hail The expression for current 3 has the form: /j2Vi.i/., JV / 3 X Л -ffcoseT where E is the voltage of a network CE} X is the resistance of one phase of the first winding TJHt $ - adjustment angle. Due to the fact that the secondary windings of the Tr4-transformer are switched in opposite to the primary windings, the current vector at the output of the VHZ rotates 360 degrees electr., i.e., remains unchanged (0 (-z) - | - | - (- Ш5 per Total current, i.e. converter output current, equal to

2

E x

(%

3

4 + COSe

From the expression (l) it can be seen, that the current is on you-. the course of the converter is independent of the change in load resistance. The level of constant current can be adjusted by turning the transformer rotor with a rotating magnetic field Tp by an angle of 0, while the rotor turns back by an angle - & (ep. hail). From the expression for the load current it can be seen that when adjusting the level of a constant current in the load, its phase relative to the voltage

F

Ormula invention

Three-phase adjustable indyktivnOich capacitive converter according to the author. St. No. 4166.8Y, characterized in that, with the goal of increasing control accuracy by stabilizing the magnitude of the phase shift between the output current and the supply voltage, it is equipped with an additional three-phase transformer with a rotating magnetic field, the primary and secondary windings of the KOTOporq are connected according to, and their connecting points E remains constant over the entire control range. The goal is achieved. Presented in FIG. 2, the vector diagram shows that the load current is out of phase with the phase voltage of the power supply: and for any. adjustment angle values c. In addition, it is clear that the proposed scheme, unlike the prototype, regulates the current in the whole range (from 0 to the maximum value). This is also the positive quality of the invention. The application of the proposed scheme does not increase the installed capacity of the elements, since each of the parallel operating transformers is performed at half the power. The appearance is consistent; from transformers TZ, Tp4 is caused by an intermittent load (plasmatron) with the mains. A matching transformer is also required when applying the prototype circuit. Experimental verification of the working ability of the proposed device and the fairness of the relationships found was carried out at a facility where phase-shifters of the FR type were used as transformers with a rotating magnetic field. "81. Synchronous rotation (rotation) of the rotors in opposite directions was carried out using an electric shaft circuit created on servomotors of the RD-09 type. The load in the experiment was a three-phase resistance. The adjustment characteristics shown in FIG. 3 show good convergence of theoretical and experimental studies, which confirms the efficiency of the circuit and the addition of the set goal. Experiments have shown that the phase of the load current with respect to the input voltage remains constant over the entire range of the control.

Dineni connected three-phase capacitor bank, ratio. peaK-J of the active resistance of each phase of which to the primary resistance of the primary winding is 3/2, the primary windings are connected to the power supply network, to the terminals of the secondary windings of the main one and to the secondary transformers are connected

primary windings of transformed transformers whose secondary windings of the same name are included anti-paraplepno, with the axes of the main and additional transformers rotors connected by a shaft, for example mechanical or electrical, providing synchronous rotation of the rotors in opposite directions.

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