SU1636832A1 - Device for stabilizing three phase ac voltage - Google Patents

Description

vector diagram showing the principle of unregulated corrected

cip action device.

The device (figure 1) contains input 1 and output 2 pins, the first 3 and second 4 three-phase booster transformers, which form the power adder (three-phase booster unit) and having respectively primary 5.6 and secondary 7.8 windings, first 9 and second 10 voltage inverters with phase switching, a three-phase uncontrolled rectifier 11, a pulse-phase control system 12, a reference element 13 and a voltage sensor 14.

20

25

voltage adjustable phase voltage

jo6 it.fr-oO uit V and% uie

which feeds the primary windings 5 and 6, respectively, of the first 3 and second 4 three-phase supercharging transformers. As a result, on the secondary windings 7 and 8 of the first and second positive-loading transformers with the same transformation ratios equal to K / 2, respectively, the voltages are applied

jtt-oc

to tt j

To tt 2 Ui

to tt v-1

The primary winding 5 of the first three-phase booster transformer 3 is connected to the star, connected in accordance with its secondary winding 7 and connected to the output of the first inverter

thirty

IV and

To tt 2 Ui

2 Uie

U,

and,

K, J0i-jol + | (e + e 3) Uf,

40

which can be converted to mind

uЈ

, +.

Booster transformers 3 and 4, summed up the voltage on the input pins 1 with the voltage of the second .... The primary windings 7 and 8 form a voltage on the torus 9 with a phase switching of 35 output pins 2 voltage. The primary winding 6 of the second three-phase booster transformer 4 is connected to a star, switched on opposite to its secondary winding 8 and connected to the output of the second voltage inverter 10 with phase switching. The secondary windings 7.8 of the first and second three-phase volt-auxiliary transformers 3,4 are connected in series and connected between the input and output terminals 1, 2, / the inputs of the first 9 and second 10 voltage inverters with phase switching are connected in parallel and A three-phase uncontrolled rectifier 11 is connected to the output terminals 2. The first and second terminals of the system 12 of the pulse-phase control, respectively, are connected to the control inputs of the first 9 and second 10 inverters on 55, with phase switching, Input C pulse 12 phase control systems through reference element 13 and

By varying the angle pt from 0 to if using a system 12 of pulse-phase control, the voltage Ua is controlled from U + KSh to U, - KUj.

Figure 2 shows a vector diagram, explaining the principle of forming voltage U, when adjusting the voltage phase in the direction of advance, relative to the input voltage at an angle of about, and the voltage phase 1B “lagging behind the input voltage same angle about

The use of the proposed device allows smoothly adjusting the output voltage up and down from the input voltage value and the dehumidification of the unregulated rectified voltage.

voltage adjustable phase voltage

jo6 it.fr-oO uit V and% uie

which feeds the primary windings 5 and 6, respectively, of the first 3 and second 4 three-phase boost transformers. As a result, on the secondary windings 7 and 8 of the first and second positive-load transformers, having the same transformation ratios equal to K / 2, the voltages are respectively

jtt-oc

to tt j

IV and

To tt 2 Ui

to tt v-1

2 Uie

U,

and,

K, J0i-jol + | (e + e 3) Uf,

windings 7 and 8, forming the same conclusions 2 voltage

which can be converted to mind

windings 7 and 8, form a voltage at the output pins 2

uЈ

, +.

Nye windings 7 and 8 single pins 2 nap

the windings of 7 and 8 form a voltage on 5 output pins 2,

By varying the angle pt from 0 to if using a system 12 of pulse-phase control, the voltage Ua is controlled from U + KSh to U, - KUj.

Figure 2 shows a vector diagram, explaining the principle of forming voltage U, when adjusting the voltage phase in the direction of advance, relative to the input voltage at an angle of about, and the voltage phase 1B “lagging behind the input voltage same angle about

Using the proposed device allows you to smoothly adjust the output voltage up and down from the input voltage and to ensure the stabilization of the alternating voltage. In this case, an increase in the stiffness of the external characteristic and an improvement in the weight and size parameters are achieved.

The use of rectifier 1I and an output voltage shaping method, in which the two invertible voltage boosters are phase-controlled in different directions with respect to the input voltage, eliminates discontinuous current mode and throttle operation of the voltage transformer 3 and 4, which increases the rigidity of the external device characteristics .

This also achieves an improvement in mass and size parameters, due to the fact that instead of three single-phase four-winding transformers of the booster unit and three input transformers, two three-phase double-winding transformers are used, the total power of which, while maintaining the control range, is 4 times less than the total power of the transformer equipment used in the known device.

When using the proposed device for voltage stabilization, there is no need for power sources of commutating capacitors of voltage inverters with phase switching, which can also be attributed to the improvement in mass and size parameters.

The use of the proposed device is most appropriate for stabilizing the voltage under load at the output of the substation substations. It is advisable to use the proposed device in electrical installations of autonomous objects, the power of sources in which is commensurate with the total power of consumers.

Claims (1)

Claims An apparatus for stabilizing a three-phase alternating voltage, comprising a three-phase booster unit, connected between the input and output terminals and having in each .1636832 0 five five up to four windings each, two voltage inverters synchronized with the input voltage control system, the input of which is connected to the output terminals through the reference element and the voltage sensor, which is due to the fact that in order to improve the weight and size parameters maintaining the output voltage control range, the rectifier is made of three-phase uncontrolled, the voltage inverters are three-phase with phase switching, and the three-phase voltage boosting unit is in the form of two three-phase voltage boosting transformers having the same transformation ratios, the secondary windings of these transformers are connected in series and connected in phase between the input and output terminals, the primary winding of the first three-phase booster transformer is connected in star, connected according to its secondary winding and connected to the output of the first inverter voltage with phase switching, the primary winding of the second three-phase booster transformer is connected in a star, switched on counter to its secondary coil and connected to the output of the second voltage inverter with phase switching, the inputs of the first and second voltage inverters with phase switching are connected in parallel and through a three-phase uncontrolled rectifier connected to the output terminals, and the pulse system is synchronized with the input voltage of the control system - but-phase control, which performs the function of the phase shift of the control pulses at the first output at an angle with relative to the input voltage, and at the second output - at the angle If -ft On angle varies from O to fr rad, wherein the first and second outputs of the pulse-phase control system connected to the control inputs of the first and vto0 five 0 five 0 ry switching inverters. phase to phase voltage KUfCOSd. U B Thebes.2 g . and