SU741245A1 - Ac voltage stabilizer - Google Patents

Description

one

The invention relates to electrical engineering and can be used in the power supply circuits of various radio engineering equipment.

A variable voltage stabilizer is known that contains primary and corrective paths. The main path contains a master oscillator and an amplifier with a controlled transmission coefficient and is intended for applying sinusoidal oscillations to the load. The correction path consists of a DC amplifier, a multiplier, and a comparison unit. The stabilizer also includes the limiting amplifier and the load. From the difference signal obtained by comparing the voltage to be stabilized with the reference rectangular signal, the multiplier is used to separate the voltage proportional to the deviation of the output signal from the nominal one, which after amplification is used to change the gain of the controlled amplifier and thus maintains the set value of the stabilized value 1 .

The closest technical solution to this invention is a device containing a master oscillator, an output connected to the input of an adjustable amplifier, the output of which is connected to the output terminal and to the input of the amplifier — body limit, an output connected to the first input of the comparator unit, the second input is connected to the output terminal, the output of the comparison unit is connected to the input of the multiplier, the output of which is connected to the first input of the adder, a DC amplifier, the output connected to the control input of the regulator Amplifier and Inverter 2.

A disadvantage of the known devices is the low stabilization accuracy.

20 in a wide frequency range due to the error of the system caused by the discrepancy between the moments of transition through the zero level of the stabilized and the reference rectangular

25 voltage.

The purpose of the invention is to improve the accuracy of stabilization in a wide range of frequencies.

. The goal is achieved by introducing an additional multiplier into the stabilizer of the alternating voltage, the first input of which is connected to the input of the limiting amplifier, the second input - to the output of the comparison unit, and the output - to the second input of the adder, the output of which is connected , and with the second input of the same adder ijfepes inverter, the output of the additional adder is connected to the input of the DC amplifier,

The drawing shows a block diagram

stabilizer variable eg.,:

I The stabilizer circuit contains an oscillator 1, the output of which is connected to the input of an adjustable force. A body 2 with a controlled transmission coefficient. The output of the latter is connected to the inputs of the amplifier-limiter 3 of the comparison unit 4, the multiplier 5 by the load 6 connected to the output terminals. The output of the limiting amplifier is supplied to the additional multiplier 7 and the comparison unit 4. The output of the comparison unit is connected to the inputs of multipliers 5 and 7, the outputs of which are connected to the adder 8, which is connected to the inputs of the inverter 9 and the additional adder 10. The output of the latter is connected to an adjustable amplifier with a controlled transmission coefficient.

The operation of this device is based on the principle of continuous comparison of the first harmonics of the output sinusoidal and rectangular reference voltages. A limiting amplifier 3 connected to the output of the stabilizer is used as a reference source. The difference signal obtained by comparing the voltage to be stabilized with the rectangular reference signal is removed from the comparison unit 4 and fed to the multipliers 5 and 7, a sinusoidal voltage is supplied to the second input of the multiplier 5 and the second reference to the second input of the multiplier 7 voltage from the output of the amplifier limiter. The output signals of the multipliers are supplied to the adder 8, at the output of which a complex voltage is obtained; the form, the constant component of KOTCjporo, does not depend on the phase shift of the compared oscillations.

The constant component of the output voltage of the multiplier 5 is equal to

5 (U3-U, K, V; aKsKaUgmUsn V K9Uim, ..

- zs ° g i

Where. H - the phase angle between

compared vibrations U / j and

  transfer ratios

comparison block and multiplier 5;

d is the voltage at the output of the stabilizer;

 voltage from the output of the limit amplifier;

U.m is the maximum value of the voltage at the output of the stabilizer;

 - the maximum value of April at the output of the amplifier limiter. In expression (1), the first term is related to the phase angle M, which causes the phase error of the stabilizer, since the angle θ varies depending on the frequency of the voltage to be stabilized.

The constant component of the output voltage of the multiplier 7, due to the multiplication of the difference signal and the first harmonic of the rectangular reference voltage, has

 u, 4u-jU,) u, - ", V

8KaKuizt 2K8K9U rT U3m ,.

where Kg is the multiplier transfer coefficient 7.

In this case, the output signal of the multiplier 7 will also have a constant component due to the multiplication of the higher harmonics of the difference signal and a rectangular reference voltage, however, this component of the multiplier 7 has a constant value, therefore the influence of the higher harmonics can be taken into account and compensate when setting up the circuit.

Sum the constant components 0 of the output voltages of the multipliers and with equal coefficients per-i. cottages, i.e. with Kg Kg, we get

..

(3)

5 where UQ is the voltage at the output of the SumI Mator 8 ..

From the last expression it follows that in the proposed scheme there is no phase error due to

0 by the discrepancy between the moments of transition through the zero level of the compared oscillations in the frequency range.

The useful signal (slowly changing constituting) from

5, the output signal of the adder 8 is separated by compensating for the higher components of the spectrum. This is achieved because / that the variable component of the spectrum is supplied to the inverter 9 of the periodic voltage,

0 required to change its phase by 180 degrees. Then, the output signals of the inverter 9 and the adder 8 are summed on the adder 10. The result of this addition is the exception

5 higher harmonics and a constant voltage isolation that is applied to an amplifier with a controlled gain and is used to restore the nominal value of a stabilized signal with high accuracy.

Claims (2)

1. USSR author's certificate 20 No. 431497, Q 05F 1/44, 1972. I 2. USSR author's certificate I 450146 Q 05 F 1/56, 1973.