CN100580605C - AC stabilivolt method using instantaneous comparison and waveform correction as well as AC stabilivolt device thereof - Google Patents

Abstract

The invention relates to an alternative current stabilization method which utilizes instant comparison and waveform correction, and a relative alternative current stabilizer. The inventive method uses a voltage stabilizing circuit to generate a control voltage with same amplitude and reversed direction of electric network voltage to counteract the fluctuation of electric network voltage. The inventive device is composed of an electric network voltage stabilizing circuit and an output voltage stabilizing circuit, wherein the electric network voltage stabilizing circuit is composed of a first sampler, a first comparator, a first amplifier, a first inversion coupling transformer and a reference voltage, and the output voltage stabilizing circuit is composed of a second sampler, a second comparator, a second amplifier, a second inversion coupling transformer and the reference voltage. The invention has the advantages of high response speed, wide input voltage application range and high stabilization precision.

Description

Adopt the AC voltage-stabilizing method and the AC stabilizer thereof of instantaneous comparison and waveform modification

Technical field

The present invention relates to a kind of AC voltage-stabilizing method and AC stabilizer thereof that adopts instantaneous comparison and waveform modification.

Background technology

The fluctuation of supply voltage is to cause one of reason of electric equipment fault, and therefore, some electric equipment need use stabilized voltage supply could ensure its normal operation.At present, Chang Yong stabilized voltage supply has servomotor to drive sliding contact formula, the variable reactor formula of adjustable transformer, the automatic voltage regulation power supply of magnetic saturation type etc.

All be to the line voltage sampling on the above-mentioned stabilized voltage supply principle, adjust through comparison process and use servomotor or noncontacting switch then, so that alternating-voltage stabilization output.The general voltage regulation result of this class stabilized voltage supply is relatively poor, and also there is following point in the precision of voltage regulation about 1%～0.5%:

(1) use the nonlinear reactance device often to bring harmonic wave, grid voltage waveform is not improved, what have also has an additional waveform distortion, and electrical network is caused harmonic pollution.

(2) sampling time and topworks are long actuation time.General effective value or the mean value of adopting is sampled, and needs several cycles at least; And it is long actuation time to carry out adjustment, needs several seconds to tens seconds as the servomotor action, and to not improvement effect of voltage waveform.These stabilized voltage supplys, to pace of change in the line voltage disturb such as surge faster, sink, impulse disturbances and high frequency interference etc. have little time reaction and carry out, and cause to disturb and pass stable-pressure device and arrive consumer, can not play a protective role to electric equipment.

Summary of the invention

Technical matters to be solved by this invention provides a kind of response speed is fast, the input voltage scope of application is wide, the precision of voltage regulation the is high instantaneous comparison of employing and the AC voltage-stabilizing method and the AC stabilizer thereof of waveform modification.

The technical solution adopted for the present invention to solve the technical problems:

(1) technical scheme 1 (adopting the AC voltage-stabilizing method of instantaneous comparison and waveform modification):

Its method step is as follows:

(1) at first by signal generator produce one with the sinusoidal wave reference voltage of line voltage with the amplitude stability of frequency, homophase

(2) to line voltage

Fluctuation carry out voltage stabilizing

A. utilize first sampling thief to line voltage Sample, the no-load voltage ratio coefficient of first sampling thief is 1/A, and the collection value of first sampling thief is

Get: $A={\stackrel{*}{U}}_s/{\stackrel{*}{U}}_r---\left(1\right)$

The electrical network rated voltage;

${\stackrel{*}{U}}_{\mathrm{in}}={\stackrel{*}{U}}_s+\mathrm{\Δ}{u}_1---\left(2\right)$

Wherein:

Line voltage

The electrical network rated voltage, the voltage under the perfect condition of electrical network regulation

Δ u ₁: the deviation value of line voltage and electrical network rated voltage;

B. the collection value that first sampling thief is gathered

With reference voltage

Carry out instantaneous comparison in first comparer, its difference is

${\stackrel{*}{U}}_{\mathrm{in}}/A-{\stackrel{*}{U}}_r=({\stackrel{*}{U}}_s+\mathrm{\Δ}{u}_1)/A-{\stackrel{*}{U}}_s/A=\mathrm{\Δ}{u}_1/A---\left(3\right)$

C. with the output voltage Δ u of first comparer ₁/ A amplifies in first amplifier, gets the enlargement factor β of first amplifier ₁=A, therefore, the output voltage of first amplifier is (Δ u ₁/ A) * β ₁=Δ u ₁

D. with the output voltage Δ u of first amplifier ₁Through no-load voltage ratio is the control voltage that 1: 1 the first reverse coupled transformer obtains ${\stackrel{*}{U}}_{\mathrm{<figure-callout\; id="1"\; label="c"\; filenames="C2008100545670014H1.png"\; state="\{\{state\}\}">c</figure-callout>}1}=-\mathrm{\&Delta;}{\mathrm{<figure-callout\; id="1"\; label="u"\; filenames="C2008100545670014H1.png"\; state="\{\{state\}\}">u</figure-callout>}}_1$ Be added in the electrical network input circuit, obtain output voltage

${\stackrel{*}{U}}_{\mathrm{out}}={\stackrel{*}{U}}_{\mathrm{in}}+{\stackrel{*}{U}}_{c1}={\stackrel{*}{U}}_{\mathrm{in}}-\mathrm{\&Delta;}{u}_1---\left(4\right)$

Formula (2) substitution formula (4) is got:

${\stackrel{*}{U}}_{\mathrm{out}}={\stackrel{*}{U}}_s---\left(5\right)$

With formula (1) and β ₁=A substitution formula (5):

${\stackrel{*}{U}}_{\mathrm{out}}={\mathrm{\&beta;}}_1{\stackrel{*}{U}}_r---\left(6\right);$

(3) at line voltage

Equal the electrical network rated voltage

Situation under, to output voltage

Fluctuation carry out voltage stabilizing;

A. utilize second sampling thief to output voltage Sample, the no-load voltage ratio coefficient of second sampling thief is 1/A; The sampled value of second sampling thief is

Get: $A={\stackrel{*}{U}}_s/{\stackrel{*}{U}}_r---\left(7\right)$

The electrical network rated voltage;

${\stackrel{*}{U}}_{\mathrm{out}}={\stackrel{*}{U}}_s+\mathrm{\&Delta;}{u}_2---\left(8\right)$

Δ u ₂: the deviation value of output voltage and electrical network rated voltage;

B. with the collection value of second sampling thief

With reference voltage

Compare in second comparer, its difference is

${\stackrel{*}{U}}_{\mathrm{out}}/A-{\stackrel{*}{U}}_r=({\stackrel{*}{U}}_s+\mathrm{\&Delta;}{u}_2)/A-{\stackrel{*}{U}}_s/A=\mathrm{\&Delta;}{u}_2/A---\left(9\right);$

C. with the output voltage Δ u of second comparer ₂/ A amplifies in second amplifier, gets the enlargement factor β of second amplifier ₂=A, therefore, the output voltage of second amplifier is (Δ u ₂/ A) * β ₂=Δ u ₂

D. with the output voltage Δ u of second amplifier ₂Through no-load voltage ratio is the control voltage that 1: 1 the second reverse coupled transformer obtains ${\stackrel{*}{U}}_{\mathrm{<figure-callout\; id="2"\; label="c"\; filenames="C2008100545670013H1.png"\; state="\{\{state\}\}">c</figure-callout>}2}=-\mathrm{\&Delta;}{\mathrm{<figure-callout\; id="2"\; label="u"\; filenames="C2008100545670013H1.png"\; state="\{\{state\}\}">u</figure-callout>}}_2$ Be added in the output circuit, obtain output voltage

${\stackrel{*}{U}}_{\mathrm{out}}={\stackrel{*}{U}}_s+\mathrm{\&Delta;}{\mathrm{<figure-callout\; id="2"\; label="u"\; filenames="C2008100545670013H1.png"\; state="\{\{state\}\}">u</figure-callout>}}_2+{\stackrel{*}{U}}_{c2}={\stackrel{*}{U}}_s---\left(10\right)$

With formula (7) and β ₂=A substitution formula (10):

${\stackrel{*}{U}}_{\mathrm{out}}={\mathrm{\&beta;}}_2{\stackrel{*}{U}}_r---\left(11\right).$

(2) technical scheme 2 (adopting the AC stabilizer of instantaneous comparison and waveform modification):

This AC stabilizer is made up of line voltage mu balanced circuit and output voltage mu balanced circuit; The line voltage mu balanced circuit is made up of first sampling thief, first comparer, first amplifier, the first reverse coupled transformer, reference voltage; The input end of first sampling thief is in parallel with line voltage, the input end of output termination first comparer of first sampling thief, reference voltage connects another input end of first comparer, the output terminal of comparer connects the input end of the first reverse coupled transformer through first amplifier, and the output terminal of the first reverse coupled transformer is connected with line voltage;

The output voltage mu balanced circuit is made up of second sampling thief, second comparer, second amplifier, the second reverse coupled transformer, described reference voltage; The input end of second sampling thief is in parallel with output voltage, the input end of output termination second comparer of second sampling thief, described reference voltage connects another input end of second comparer, the output terminal of second comparer connects the input end of the second reverse coupled transformer through second amplifier, and the output terminal of the second reverse coupled transformer is connected with output voltage;

Described reference voltage is a sine wave that produced by signal generator and the amplitude stability same frequency of line voltage, homophase.

Beneficial effect of the present invention is as follows:

(1) response speed is fast.Since select high-speed electronic components for use, instantaneous sampling, instantaneous execution, and control response speed is exceedingly fast, can finish adjustment below the Millisecond, therefore inhibited for high frequency interference and noise, interference has clean-up effect to Millisecond, and this is that general stabilized voltage supply is not accomplished.

(2) the input voltage scope of application is wide.Can reach 30%～50% even more, and the symmetry adjusting, the wide more need of scope provide the repairing energy many more.Control voltage value is mainly decided by demand,, gets (8～10) % from economical and practical angle and is advisable.

(3) precision of voltage regulation height.With the difference of reference voltage, the precision of voltage regulation can reach 1%, 0.1%, 0.01%.The voltage stabilizing of different accuracy is suitable for the different occasions that require.

The precision of voltage regulation is 1% to be used for general voltage stabilizing requirement occasion; The precision of voltage regulation is 0.1% to be used for laboratory or important commercial unit; The precision of voltage regulation is 0.01% to can be used for instrument calibration.

(4) has the feature of green power supply.This method is at first revised the waveform insufficient section of line voltage, is modified to good sine wave, load is powered again.What needing, what are mended, repair energy and how much determine by needs.Because this method is the repairing to the electrical network waveform, revise good waveform distortion and be generally less than 1% or 0.5%, therefore say that this method for stabilizing voltage is green.

(5) has the character of environmental protection power supply.If input voltage is constant, because causing output voltage, the difference of load characteristic changes, in certain harmonic wave scope, utilize the corresponding change of control voltage to make output voltage constant, because control voltage has buffer action, do not affect line voltage.Therefore, this kind method for stabilizing voltage has the feature of environmental protection.

(6) high efficiency.The principle of work of this power supply is that miniwatt control is high-power, has very high efficient.The capacity of output voltage is mainly taken from electrical network, and control voltage generally is the part that line voltage departs from rated voltage, thus only need consume the power of production control power supply, so the efficient height.

(7) do not use low frequency filtering devices such as big inductance, big electric capacity, machine volume is less comparatively speaking, and output waveform is good.

(8) this principle of stabilized voltage can with other voltage stabilizer cascade.

(9) can use fast protection circuit.When load end instantaneous short-circuit fault, the control power supply is deactivated at once, and at this moment, the reverse coupled transformer is equivalent to a reactor, has the effect that limiting short-circuit current increases, and after fault was eliminated, the control power supply was resumed work voluntarily.

Description of drawings

Fig. 1 is the principle schematic of AC voltage-stabilizing method of the present invention.

Fig. 2 is a principle calcspar of the present invention.

Fig. 3 is the circuit theory diagrams of AC stabilizer of the present invention.

Embodiment

Embodiment 1 (embodiment of AC voltage-stabilizing method):

As shown in Figure 1, 2, the method step of AC voltage-stabilizing method of the present invention is as follows:

(1) at first by signal generator produce one with the sinusoidal wave reference voltage of line voltage with the amplitude stability of frequency, homophase

(2) to line voltage

Fluctuation carry out voltage stabilizing

A. utilize first sampling thief to line voltage

Sample, the no-load voltage ratio coefficient of first sampling thief is 1/A, and the collection value of first sampling thief is

Get: $A={\stackrel{*}{U}}_s/{\stackrel{*}{U}}_r---\left(1\right)$

The electrical network rated voltage;

${\stackrel{*}{U}}_{\mathrm{in}}={\stackrel{*}{U}}_s+\mathrm{\&Delta;}{u}_1---\left(2\right)$

Wherein:

Line voltage

The electrical network rated voltage, the voltage under the perfect condition of electrical network regulation

Δ u ₁: the deviation value of line voltage and electrical network rated voltage;

B. the collection value that first sampling thief is gathered

With reference voltage

Carry out instantaneous comparison in first comparer, its difference is

${\stackrel{*}{U}}_{\mathrm{in}}/A-{\stackrel{*}{U}}_r=({\stackrel{*}{U}}_s+\mathrm{\&Delta;}{u}_1)/A-{\stackrel{*}{U}}_s/A=\mathrm{\&Delta;}{u}_1/A---\left(3\right)$

C. with the output voltage Δ u of first comparer ₁/ A amplifies in first amplifier, gets the enlargement factor β of first amplifier ₁=A, therefore, the output voltage of first amplifier is (Δ u ₁/ A) * β ₁=Δ u ₁

D. with the output voltage Δ u of first amplifier ₁Through no-load voltage ratio is the control voltage that 1: 1 the first reverse coupled transformer obtains ${\stackrel{*}{U}}_{\mathrm{<figure-callout\; id="1"\; label="c"\; filenames="C2008100545670014H1.png"\; state="\{\{state\}\}">c</figure-callout>}1}=-\mathrm{\&Delta;}{\mathrm{<figure-callout\; id="1"\; label="u"\; filenames="C2008100545670014H1.png"\; state="\{\{state\}\}">u</figure-callout>}}_1$ Be added in the electrical network input circuit, obtain output voltage

${\stackrel{*}{U}}_{\mathrm{out}}={\stackrel{*}{U}}_{\mathrm{in}}+{\stackrel{*}{U}}_{\mathrm{<figure-callout\; id="1"\; label="c"\; filenames="C2008100545670014H1.png"\; state="\{\{state\}\}">c</figure-callout>}1}={\stackrel{*}{U}}_{\mathrm{in}}-\mathrm{\&Delta;}{u}_1---\left(4\right)$

Formula (2) substitution formula (4) is got:

${\stackrel{*}{U}}_{\mathrm{out}}={\stackrel{*}{U}}_s---\left(5\right)$

With formula (1) and β ₁=A substitution formula (5):

${\stackrel{*}{U}}_{\mathrm{out}}={\mathrm{\&beta;}}_1{\stackrel{*}{U}}_r---\left(6\right);$

(3) at line voltage

Equal the electrical network rated voltage

Situation under, to output voltage

Fluctuation carry out voltage stabilizing;

A. utilize second sampling thief to output voltage

Sample, the no-load voltage ratio coefficient of second sampling thief is 1/A; The sampled value of second sampling thief is

Get: $A={\stackrel{*}{U}}_s/{\stackrel{*}{U}}_r---\left(7\right)$

The electrical network rated voltage;

${\stackrel{*}{U}}_{\mathrm{out}}={\stackrel{*}{U}}_s+\mathrm{\&Delta;}{u}_2---\left(8\right)$

Δ u ₂: the deviation value of output voltage and electrical network rated voltage;

B. with the collection value of second sampling thief

With reference voltage

Compare in second comparer, its difference is

${\stackrel{*}{U}}_{\mathrm{out}}/A-{\stackrel{*}{U}}_r=({\stackrel{*}{U}}_s+\mathrm{\&Delta;}{u}_2)/A-{\stackrel{*}{U}}_s/A=\mathrm{\&Delta;}{u}_2/A---\left(9\right);$

C. with the output voltage Δ u of second comparer ₂/ A amplifies in second amplifier, gets the enlargement factor β of second amplifier ₂=A, therefore, the output voltage of second amplifier is (Δ u ₂/ A) * β ₂=Δ u ₂

D. with the output voltage Δ u of second amplifier ₂Through no-load voltage ratio is the control voltage that 1: 1 the second reverse coupled transformer obtains ${\stackrel{*}{U}}_{\mathrm{<figure-callout\; id="2"\; label="c"\; filenames="C2008100545670013H1.png"\; state="\{\{state\}\}">c</figure-callout>}2}=-\mathrm{\&Delta;}{\mathrm{<figure-callout\; id="2"\; label="u"\; filenames="C2008100545670013H1.png"\; state="\{\{state\}\}">u</figure-callout>}}_2$ Be added in the output circuit, obtain output voltage

${\stackrel{*}{U}}_{\mathrm{out}}={\stackrel{*}{U}}_s+\mathrm{\&Delta;}{\mathrm{<figure-callout\; id="2"\; label="u"\; filenames="C2008100545670013H1.png"\; state="\{\{state\}\}">u</figure-callout>}}_2+{\stackrel{*}{U}}_{\mathrm{<figure-callout\; id="2"\; label="c"\; filenames="C2008100545670013H1.png"\; state="\{\{state\}\}">c</figure-callout>}2}={\stackrel{*}{U}}_s---\left(10\right)$

With formula (7) and β ₂=A substitution formula (10):

${\stackrel{*}{U}}_{\mathrm{out}}={\mathrm{\&beta;}}_2{\stackrel{*}{U}}_r---\left(11\right).$

The principle of the inventive method is as shown in Figure 1:

In Fig. 1, ${\stackrel{*}{U}}_{\mathrm{in}}={\stackrel{*}{U}}_s+\mathrm{\&Delta;}{\mathrm{<figure-callout\; id="1"\; label="u"\; filenames="C2008100545670014H1.png"\; state="\{\{state\}\}">u</figure-callout>}}_1$

Line voltage

The electrical network rated voltage, the rated voltage effective value of single-phase alternating current is 220V

Δ u ₁: the deviation value of line voltage and electrical network rated voltage

${\stackrel{*}{U}}_{\mathrm{out}}={\stackrel{*}{U}}_{\mathrm{in}}+{\stackrel{*}{U}}_{\mathrm{<figure-callout\; id="1"\; label="c"\; filenames="C2008100545670014H1.png"\; state="\{\{state\}\}">c</figure-callout>}1}$

Output voltage

Control voltage

When control voltage ${\stackrel{*}{U}}_{\mathrm{<figure-callout\; id="1"\; label="c"\; filenames="C2008100545670014H1.png"\; state="\{\{state\}\}">c</figure-callout>}1}=-\mathrm{\&Delta;}{\mathrm{<figure-callout\; id="1"\; label="u"\; filenames="C2008100545670014H1.png"\; state="\{\{state\}\}">u</figure-callout>}}_1$ The time,

${\stackrel{*}{U}}_{\mathrm{out}}={\stackrel{*}{U}}_{\mathrm{in}}+{\stackrel{*}{U}}_{\mathrm{<figure-callout\; id="1"\; label="c"\; filenames="C2008100545670014H1.png"\; state="\{\{state\}\}">c</figure-callout>}1}={\stackrel{*}{U}}_s+\mathrm{\&Delta;}{u}_1-\mathrm{\&Delta;}{\mathrm{<figure-callout\; id="1"\; label="u"\; filenames="C2008100545670014H1.png"\; state="\{\{state\}\}">u</figure-callout>}}_1={\stackrel{*}{U}}_s$

Can draw by following formula: when control voltage Amplitude equal the undulating quantity Δ u of line voltage ₁, and direction when opposite, output voltage

Equal the electrical network rated voltage

Method of the present invention is exactly to produce an above-mentioned control voltage by mu balanced circuit

Make output voltage With line voltage Fluctuation irrelevant.

Embodiment 2 (AC stabilizer):

By Fig. 2,3 as can be known, present embodiment 2 described AC stabilizer are made up of line voltage mu balanced circuit and output voltage mu balanced circuit; The line voltage mu balanced circuit is made up of first sampling thief, first comparer, first amplifier, the first reverse coupled transformer, reference voltage; The input end of first sampling thief is in parallel with line voltage, the input end of output termination first comparer of first sampling thief, reference voltage connects another input end of first comparer, the output terminal of comparer connects the input end of the first reverse coupled transformer through first amplifier, and the output terminal of the first reverse coupled transformer is connected with line voltage;

The output voltage mu balanced circuit is made up of second sampling thief, second comparer, second amplifier, the second reverse coupled transformer, described reference voltage; The input end of second sampling thief is in parallel with output voltage, the input end of output termination second comparer of second sampling thief, described reference voltage connects another input end of second comparer, the output terminal of second comparer connects the input end of the second reverse coupled transformer through second amplifier, and the output terminal of the second reverse coupled transformer is connected with output voltage;

Described reference voltage is a sine wave that produced by signal generator and the amplitude stability same frequency of line voltage, homophase.

First sampling thief of described line voltage mu balanced circuit is made up of voltage transformer (VT) T1, and the no-load voltage ratio coefficient of voltage transformer (VT) T1 is 1/A, the elementary and line voltage of voltage transformer (VT) T1 In parallel;

Described first comparer is made up of operational amplifier IC1, resistance R 1～R4, negative input 2 pin of operational amplifier IC1 connect an end of T1 level of voltage transformer (VT) through resistance R 1, the other end ground connection of T1 level of voltage transformer (VT), positive input 3 pin of operational amplifier IC1 connect reference voltage through resistance R 2

An end, reference voltage

Other end ground connection, resistance R 4 is connected between 3 pin and ground of operational amplifier IC1, resistance R 3 is connected between 2 pin and 6 pin and ground of operational amplifier IC1;

Described first amplifier is made up of voltage amplifier and power amplifier, the enlargement factor β of first amplifier ₁=A; Described voltage amplifier is made up of operational amplifier IC2, resistance R 5～R7, negative input 2 pin of operational amplifier IC2 connect output terminal 6 pin of operational amplifier IC1 through resistance R 5, resistance R 7 is connected between 3 pin and ground of operational amplifier IC2, and resistance R 6 is connected between 2 pin and 6 pin of operational amplifier IC2; Described power amplifier is the push-pull amplifier of being made up of transistor Q1, Q2, coupling transformer T2, resistance R 8～R10, coupling transformer T2 elementary is connected between output terminal 6 pin and ground of operational amplifier IC2, the secondary base stage that meets transistor Q1 and Q2 respectively of coupling transformer T2, the center tap of T2 level of coupling transformer connect Vcc1 and ground through resistance R 8 and R9 respectively; The emitter parallel connection of transistor Q1 and Q2 is after resistance R 10 ground connection; The collector of transistor Q1 and Q2 connects the elementary of the described first reverse coupled transformer T3 (its no-load voltage ratio coefficient is 1: 1) respectively, the elementary center tap of the described first reverse coupled transformer T3 meets Vcc1, and the secondary and line voltage of the described first reverse coupled transformer T3 is connected.

The structure identical (its circuit theory diagrams are seen Fig. 3) of the structure of described output voltage mu balanced circuit and line voltage mu balanced circuit.The no-load voltage ratio coefficient of second sampling thief is 1/A; The enlargement factor of second amplifier is β ₂=A; The no-load voltage ratio coefficient of the second reverse coupled transformer is 1: 1.

Claims (4)

1. adopt the AC voltage-stabilizing method of instantaneous comparison and waveform modification, it is characterized in that its method step is as follows:

(1) at first by signal generator produce one with the sinusoidal wave reference voltage of line voltage with the amplitude stability of frequency, homophase

(2) to line voltage Fluctuation carry out voltage stabilizing

A. utilize first sampling thief to line voltage Sample, the no-load voltage ratio coefficient of first sampling thief is 1/A, and the collection value of first sampling thief is

Get:

The electrical network rated voltage;

Wherein: Line voltage

The electrical network rated voltage, the voltage under the perfect condition of electrical network regulation

Δ u ₁: the deviation value of line voltage and electrical network rated voltage;

B. the collection value that first sampling thief is gathered

With reference voltage

Carry out instantaneous comparison in first comparer, its difference is

C. with the output voltage Δ u of first comparer ₁/ A amplifies in first amplifier, gets the enlargement factor β of first amplifier ₁=A, therefore, the output voltage of first amplifier is (Δ u ₁/ A) * β ₁=Δ u ₁

D. with the output voltage Δ u of first amplifier ₁Through no-load voltage ratio is the control voltage that 1: 1 the first reverse coupled transformer obtains

Be added in the electrical network input circuit, obtain output voltage

Formula (2) substitution formula (4) is got:

With formula (1) and β ₁=A substitution formula (5):

(3) at line voltage

Equal the electrical network rated voltage

Situation under, to output voltage

Fluctuation carry out voltage stabilizing;

A. utilize second sampling thief to output voltage Sample, the no-load voltage ratio coefficient of second sampling thief is 1/A; The sampled value of second sampling thief is

Get:

The electrical network rated voltage;

Δ u ₂: the deviation value of output voltage and electrical network rated voltage;

B. with the collection value of second sampling thief With reference voltage Compare in second comparer, its difference is

C. with the output voltage Δ u of second comparer ₂/ A amplifies in second amplifier, gets the enlargement factor β of second amplifier ₂=A, therefore, the output voltage of second amplifier is (Δ u ₂/ A) * β ₂=Δ u ₂

D. with the output voltage Δ u of second amplifier ₂Through no-load voltage ratio is the control voltage that the second reverse coupled transformer of 1:1 obtains Be added in the output circuit, obtain output voltage

With formula (7) and β ₂=A substitution formula (10):

2. adopt the AC stabilizer of instantaneous comparison and waveform modification, it is characterized in that it is made up of line voltage mu balanced circuit and output voltage mu balanced circuit; The line voltage mu balanced circuit is made up of first sampling thief, first comparer, first amplifier, the first reverse coupled transformer, reference voltage; The input end of first sampling thief is in parallel with line voltage, the input end of output termination first comparer of first sampling thief, reference voltage connects another input end of first comparer, the output terminal of comparer connects the input end of the first reverse coupled transformer through first amplifier, and the output terminal of the first reverse coupled transformer is connected with line voltage;

The output voltage mu balanced circuit is made up of second sampling thief, second comparer, second amplifier, the second reverse coupled transformer, described reference voltage; The input end of second sampling thief is in parallel with output voltage, the input end of output termination second comparer of second sampling thief, described reference voltage connects another input end of second comparer, the output terminal of second comparer connects the input end of the second reverse coupled transformer through second amplifier, and the output terminal of the second reverse coupled transformer is connected with output voltage;

Described reference voltage is a sine wave that produced by signal generator and the amplitude stability same frequency of line voltage, homophase.

3. according to the AC stabilizer of instantaneous comparison of the described employing of claim 2 and waveform modification, first sampling thief of described line voltage mu balanced circuit is made up of voltage transformer (VT) T1, the elementary and line voltage of voltage transformer (VT) T1

In parallel;

Described first comparer is made up of operational amplifier IC1, resistance R 1～R4, negative input 2 pin of operational amplifier IC1 connect an end of T1 level of voltage transformer (VT) through resistance R 1, the other end ground connection of T1 level of voltage transformer (VT), positive input 3 pin of operational amplifier IC1 connect reference voltage through resistance R 2

An end, reference voltage

Other end ground connection, resistance R 4 is connected between 3 pin and ground of operational amplifier IC1, resistance R 3 is connected between 2 pin and 6 pin and ground of operational amplifier IC1;

Described first amplifier is made up of voltage amplifier and power amplifier; Described voltage amplifier is made up of operational amplifier IC2, resistance R 5～R7, negative input 2 pin of operational amplifier IC2 connect output terminal 6 pin of operational amplifier IC1 through resistance R 5, resistance R 7 is connected between 3 pin and ground of operational amplifier IC2, and resistance R 6 is connected between 2 pin and 6 pin of operational amplifier IC2; Described power amplifier is the push-pull amplifier of being made up of transistor Q1, Q2, coupling transformer T2, resistance R 8～R10, coupling transformer T2 elementary is connected between output terminal 6 pin and ground of operational amplifier IC2, the secondary base stage that meets transistor Q1 and Q2 respectively of coupling transformer T2, the center tap of T2 level of coupling transformer connect Vcc1 and ground through resistance R 8 and R9 respectively; The emitter parallel connection of transistor Q1 and Q2 is after resistance R 10 ground connection; The collector of transistor Q1 and Q2 connects the elementary of the described first reverse coupled transformer T3 respectively, and the elementary center tap of the described first reverse coupled transformer T3 meets Vcc1, and the secondary and line voltage of the described first reverse coupled transformer T3 is connected.

4. the AC stabilizer of instantaneous comparison of employing according to claim 3 and waveform modification is characterized in that the structure of described output voltage mu balanced circuit is identical with the structure of line voltage mu balanced circuit.

Images