SU363184A1 - ^? C? ^ UNION - Google Patents

Description

one

The invention can be used in automation devices for measuring and setting the phase of an alternating electrical voltage.

In the known phase shifters using a rotating transformer, in the sine and cosine windings of which phase-shifting bridges with different time constants are included, an additional active-reactive circuit is used to reduce the error from the frequency variation of the supply voltage. Such a phase shifter is characterized by a significant error when changing the frequency of the supply voltage in excess of 30%.

The purpose of the invention is to reduce the phase shifter error caused by a change in the frequency of the supply voltage of the phase shifter.

To this end, the proposed phase shifter to extreme conclusions cosine and sine windings of the rotary transformer are connected in series connected resistor and capacitor, the junction point of which and the midpoints of the cosine and sine windings of the rotary transformer is connected to the input diagonals of the phase-shifting bridges, the output diagonal of which through matching devices connected respectively to the input windings of the transformer and inverting transformer.

The drawing shows a diagram of the proposed phase shifter.

The phase shifter consists of a rotating transformer containing a sine stator /, cosine stator 2 n rotor 5 windings.

The capacitor 4 and the resistor 5 are connected to the sinus winding I and form, with its midpoint, the first active-reactive bridge circuit, the time constant of which is set to

five

and

c, sya

15

where W is the nominal angular frequency of the voltage supply to the phase shifter.

The capacitor 6 n resistor 7 is connected to the cosine winding 2 and with its midpoint form a second active-reactive bridge circuit whose time constant is equal to

3

tP l

 sixteen

 WITH,.,

W

To the OUTPUT diagonal of the first bridge circuit is connected a phase-shifting bridge made up of a resistor 8, a capacitor 9 and two 30 equal in size (to form a midpoint) resistors 10 and 11. The time constant of this bridge circuit is 8 9 - K output diagonal of the second bridge circuit Another phase-shifted bridge circuit is connected, consisting of resistor 12, capacitor 13 and two identical resistances 14 and 15. The time constant of this bridge circuit is equal. The resistance value of the elements of phase-shifting bridges is considerable greater than the resistances of the first and second bridge circuits. The output diagonal phase-shifting bridges are connected to the inputs of the matching devices 16 and 17, which can be used as cathode repeaters. A phase inverter in the form of transformer 18 is connected to the output of the matching device 16, and a noninventing transformer 19 is connected to the output of the matching device 17. Transformer 18 contains a primary 20, which injects secondary 21 and secondary 22 windings, and a transformer 19 - primary 23 and two secondary 24 and 25 windings. The windings 21 and 25 are connected in series and counter and form the first output of the Ui phase shifter. The windings 22 and 24 are connected in series according to and form the second output of the U2 phase shifter. Phaser works as follows. The rotor winding 3 of the rotating transformer is energized by a sinusoidal voltage f / Bx with an angular frequency W. When the rotor winding rotates through an angle and the phase / output voltage Ui changes relative to the output voltage Uz, the law of the proposed phase shifter arises when the voltage frequency changes that turns a phase shifter, it is determined that E - (- - 2 P, 1 + 8/16 + 64d + 1122 + 112 + 70 + 28 | + 7 + D (A is the relative detuning of the frequency of the supply voltage of the phase shifter). For example, at frequency detuning three times (D 2) phase error The magnitude of the output voltages of the proposed phase shifter with frequency detuning is changed but less compared to the prototype. Subject of the invention The phase shifter containing a rotating transformer, phase-shifting bridges, matching devices, a transformer and an inverting transformer, in order to reduce Errors from a change in the frequency of the supply voltage, to the extreme terminals of the cosine and sine windings of a rotating transformer, connected in series are connected the stopper and capacitor, the connection points of which and the midpoints of the cosine and sine windings of the rotating transformer are connected to the input diagonal of the phase-shifting bridges, the output diagonals of which through the matching devices are connected to the input windings of the transformer and inverting transformer respectively.

and.