CN109765955A - A kind of Voltage Feedback control circuit - Google Patents
A kind of Voltage Feedback control circuit Download PDFInfo
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- CN109765955A CN109765955A CN201811492395.6A CN201811492395A CN109765955A CN 109765955 A CN109765955 A CN 109765955A CN 201811492395 A CN201811492395 A CN 201811492395A CN 109765955 A CN109765955 A CN 109765955A
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Abstract
The invention discloses a kind of Voltage Feedback control circuits, belong to Voltage Feedback control field, and the present invention realizes fast sampling to output voltage by voltage sample circuit, collected output voltage is sent to automatic gain amplifying circuit；Amplified by automatic gain and is controlled, the transfer ratio of isolation and transmission circuit, and then the duty ratio of adjusting pulsewidth modulator are adjusted, realizes the quick pressure stabilizing control of the high-precision of out-put supply, biasing accelerates the voltage change of control circuit while sensing feed-back output end, realizes output quickly dynamic adjustment.The present invention uses quick response voltage sample circuit, avoids voltage dynamic transients and responds insufficient problem；Using automatic gain feedback control technology, output voltage precision is improved, the higher-order of oscillation is effectively eliminated；Driving circuit is accelerated using biasing, improves output adjustment ability, avoids output over control.
Description
Technical field
The invention belongs to Voltage Feedback control fields, and in particular to a kind of Voltage Feedback control circuit.
Background technique
Conventional Voltage Feedback control circuit generally uses electric resistance partial pressure feedback control circuit, this voltage feedback circuit because
Convenient to realize, structure is simple, is widely adopted.But when load is non-resistive capacity load or inductive load,
This conventional electric resistance partial pressure type voltage feedback control circuit will be unable to meet the needs of output voltage quickly adjusts control.Especially
It is the high-end power supply more demanding in load effect, output response etc., snap switch load capacity, output dynamic to power supply
Response speed, the precision of voltage regulation, more stringent requirements are proposed for high frequency ripple noise.To exporting, dynamic response requirement is higher to be answered for these
With occasion, the design difficulty of Voltage Feedback control circuit is increased.Therefore, it is necessary to study novel Voltage Feedback control circuit,
To solve problems.
Summary of the invention
For the above-mentioned technical problems in the prior art, the invention proposes a kind of Voltage Feedback control circuits, if
Meter rationally, overcomes the deficiencies in the prior art, has good effect.
To achieve the goals above, the present invention adopts the following technical scheme:
A kind of Voltage Feedback control circuit, including voltage sample circuit, automatic gain amplifying circuit, isolation transmission control electricity
Road and biasing accelerate control circuit；
Voltage sample circuit is configurable for being acquired output voltage, and collected output voltage is exported
To automatic gain amplifying circuit；
Automatic gain amplifying circuit is configurable for adjusting the transfer ratio of isolation control transmission circuit, and then adjusts arteries and veins
The duty ratio of wide modulator；
Transmission control circuit is isolated, is configurable for the primary of driving isolation and transmission circuit, controls pulse width modulator
Pulse width；
Biasing accelerates control circuit, is configurable for the voltage fluctuation of feedback output end, realizes that rapid overpressure protects function
Energy.
Preferably, voltage sample circuit, including first resistor, second resistance, 3rd resistor, the 4th resistance, first capacitor
With first voltage source Vout+；One end of first resistor is connected to first voltage source Vout+, the other end and second resistance of first resistor
One end composition common end be connected to one end of the 4th resistance, the other end of the 4th resistance is connected with one end of first capacitor, the
One end of the other ends of two resistance and 3rd resistor composition common end is connected to the other end of first capacitor, 3rd resistor it is another
End ground connection.
Preferably, biasing accelerates control circuit, including the 6th resistance, the 7th resistance, the 8th resistance, the 4th capacitor, NPN tri-
Pole pipe and the second voltage source+Vcc；One end of 6th resistance and one end composition common end of the 7th resistance are connected to the 4th resistance
One end, the other end of the 7th resistance are connected to one end of the 4th capacitor, the other end of the 4th capacitor, the other end of the 6th resistance and
One end composition common end of 8th resistance is connected to the base stage of NPN triode, the other end ground connection of the 8th resistance, NPN triode
Collector be connected to the second voltage source+Vcc.
Preferably, automatic gain amplifying circuit, including the 5th resistance, the tenth resistance, the second capacitor, third capacitor, operation
Amplifier and reference voltage Vref；One end of tenth resistance and one end composition common end of the second capacitor are connected to first capacitor
The other end of the other end, the tenth resistance is connected to the inverting input terminal of operational amplifier；The other end and the third electricity of second capacitor
One end composition common end of appearance is connected to one end of the 5th resistance, the other end composition of the other end of third capacitor and the 5th resistance
Common end is connected to the output end of operational amplifier, and the non-inverting input terminal of operational amplifier is connected to reference voltage Vref.
Preferably, isolation and transmission circuit, including the 9th resistance and photoelectrical coupler；One end of 9th resistance is connected to NPN
The emitter of triode, the other end of the 9th resistance are connected to the first input end of photoelectrical coupler, and the second of photoelectrical coupler
Input terminal is connected to the output end of operational amplifier, and the first output end of photoelectrical coupler is connected to pulse width modulator, photoelectricity coupling
The second output terminal of clutch is grounded.
Advantageous effects brought by the present invention:
1, using quick response voltage sample circuit, voltage dynamic transients is avoided and respond insufficient problem.
2, using automatic gain feedback control technology, output voltage precision is improved, the higher-order of oscillation is effectively eliminated.
3, driving circuit is accelerated using biasing, improves output adjustment ability, avoid output over control.
A kind of Voltage Feedback control circuit of the present invention and method, specifically a kind of Voltage Feedback using quick response technology
Control circuit and method；The circuit can not only realize the reliable control function of Voltage Feedback, and even if work higher
Under switching frequency, circuit control is also sufficiently stable；The circuit is particularly with non-resistive capacity load or inductive load
Output feedback ontrol has unrivaled superiority, so that the voltage regulation factor of supply convertor, load regulation and wink
The performance indicators such as state response have breakthrough raising, improve the dynamic response performance of circuit.
Detailed description of the invention
Fig. 1 is the functional block diagram of Voltage Feedback control circuit of the present invention.
Fig. 2 is the schematic diagram of Voltage Feedback control circuit of the present invention.
Specific embodiment
With reference to the accompanying drawing and specific embodiment invention is further described in detail:
As shown in Figure 1, a kind of Voltage Feedback control circuit, including voltage sample circuit, automatic gain amplifying circuit, isolation
Transmission control circuit and biasing accelerate control circuit；Voltage sample circuit realizes fast sampling to output voltage, will be collected
Output voltage is sent to automatic gain amplifying circuit；Amplified by automatic gain and controlled, adjusts the transfer ratio of isolation and transmission circuit, into
And the duty ratio of adjusting pulsewidth modulator, realize the quick pressure stabilizing control of the high-precision of out-put supply.Biasing accelerates control circuit same
When sensing feed-back output end voltage fluctuation, realize rapid overpressure defencive function.Wherein, voltage sample circuit, due to using
Sampling method is coupled, alternating current voltage sampling speed and partial pressure coefficient in output voltage is increased, effectively increases dynamic response
Speed with exchange rejection ability, the transient state for improving power supply is regulated the speed and high frequency ripple index.Automatic gain amplifying circuit
Operational amplification circuit amplifies voltage sampling signal, and automatic gain feed circuit becomes according to output voltage and actual loading
Change, carries out the automatic growth control of respective quadrature, direct voltage component；DC current gain is equivalent to the open-loop gain of operational amplifier,
Effectively improve the precision of output voltage；High-frequency gain is equivalent to the closed loop gain of operational amplifier, and gain coefficient is less than 1, effectively
Inhibit high-frequency gain, eliminates the higher-order of oscillation.Isolation drive control circuit drives the primary of isolation and transmission circuit, then is passed by isolation
The pulse width of defeated circuit control PWM, to reach the high precision adjustment control of output voltage.In addition, accelerating control for biasing
Circuit processed significantly improves transient response performance, it is existing to can effectively avoid output voltage overshoot due to using high frequency acceleration technique
As.
As shown in Fig. 2, voltage sample circuit, including first resistor R1, second resistance R2,3rd resistor R3, the 4th resistance
R4, first capacitor C1 and first voltage source Vout+；One end of first resistor R1 is connected to first voltage source Vout+, first resistor R1
The other end and one end composition common end of second resistance R2 be connected to one end of the 4th resistance R4, the other end of the 4th resistance R4
It is connected with one end of first capacitor C1, one end composition common end of the other end of second resistance R2 and 3rd resistor R3 are connected to the
The other end of one capacitor C1, the other end ground connection of 3rd resistor R3.
For voltage sample circuit, voltage sample circuit using DC voltage sample with exchange accelerate sample combine take
Quadrat method.Wherein, second resistance R2 resistance value is tens kilohms, and the 4th resistance value R4 is several kilohms, and first resistor R1 resistance value is only
It is tens ohm, for long line damping resistance, has and eliminate long line oscillation action.Second resistance R2,3rd resistor R3 composition feedback
Partial pressure；4th R4, first capacitor C1 form capacitive coupling and accelerate feedback；Second resistance R2,3rd resistor R3 and the 4th resistance R4,
First capacitor C1 collectively forms the feedback partial pressure of high frequency voltage ingredient.In the present invention, power switch Frequency Design is 200kHz, the
The one equivalent capacitive reactance of capacitor C1 is only several ohm, and for high frequency ripple voltage, sampling rate is clearly to be greater than direct current sampling rate.Can have
Effect improves load effect and transient response performance.
Automatic gain amplifying circuit, including the 5th resistance R5, the tenth resistance R10, the second capacitor C2, third capacitor C3, fortune
Calculate amplifier N1 and reference voltage Vref；One end of tenth resistance R10 and one end of the second capacitor C2 composition common end are connected to
The other end of the other end of first capacitor C1, the tenth resistance R10 is connected to the inverting input terminal of operational amplifier N1；Second capacitor
The other end of C2 and one end composition common end of third capacitor C3 are connected to one end of the 5th resistance R5, and third capacitor C3's is another
The other end of end and the 5th resistance R5 composition common end are connected to the output end of operational amplifier N1, the same phase of operational amplifier N1
Input terminal is connected to reference voltage Vref；
For automatic gain amplifying circuit, feedback characteristics is: with the raising of frequency, gain reduction.Direct current is believed
Number, since the equivalent impedance of the second capacitor C2 is infinitely great, gain is equivalent to the open-loop gain of operational amplification circuit, and DC current gain is high
Up to 100dB or more；Frequency increases again, and feedback impedance is successively mainly determined by third capacitor C3 equivalent impedance, the 5th resistance R5 impedance
Fixed, gain reduces gradually；Until being equivalent to " zero " impedance, it is 1 that the working condition of operational amplifier, which is equivalent to gain coefficient, at this time
Follower state.It can be seen that the circuit equivalent is in automatic gain feedback control circuit varying with frequency.To realize
The automatic growth control of AC and DC voltage component, reaches the high precision adjustment control of output voltage, while improving the moment of circuit
Band carries regulating power, output dynamic responding speed and the precision of voltage regulation, high frequency ripple noise etc..
Isolation and transmission circuit, including the 9th resistance R9 and photoelectrical coupler E1；One end of 9th resistance R9 is connected to NPN tri-
The emitter of pole pipe V1, the other end of the 9th resistance R9 are connected to the first input end of photoelectrical coupler E1, photoelectrical coupler E1
The second input terminal be connected to the output end of operational amplifier N1, the first output end of photoelectrical coupler E1 is connected to pulsewidth modulation
Device, the second output terminal ground connection of photoelectrical coupler E1.
Operational amplifier N1 determines the primary on state of photoelectrical coupler E1, and the 9th resistance R9 plays limitation photoelectric coupling
The primary conducting electric current of device E1 acts on, and photoelectrical coupler E1 carries out primary and secondary transmission current control function.Specific work process
Be: when output voltage is lower than setting voltage, operational amplifier N1 output tends to be high voltage, and photoelectrical coupler E1 tends to cut
Only, the duty ratio of pulse width modulator increases, and output voltage increases；When output voltage is higher than setting voltage, operational amplifier N1
Output tends to be low-voltage, and photoelectrical coupler E1 tends to conducting, and the duty ratio of pulse width modulator reduces, and output voltage reduces.From
And realize the pressure stabilizing control of output voltage.In addition, isolation and transmission circuit transmits control model using electric current, output can be not only realized
The reliable pressure stabilizing of voltage controls, and power supply Earth noise can be effectively reduced to the unfavorable shadow of control precision and control reliability
It rings.
Biasing accelerates control circuit, including the 6th resistance R6, the 7th resistance R7, the 8th resistance R8, the 4th capacitor C4, NPN
Triode V1 and the second voltage source+Vcc；One end of 6th resistance R6 and one end of the 7th resistance R7 composition common end are connected to the
One end of four resistance R4, the other end of the 7th resistance R7 are connected to one end of the 4th capacitor C4, the other end of the 4th capacitor C4,
The other end of six resistance R6 and one end composition common end of the 8th resistance R8 are connected to the base stage of NPN triode V1, the 8th resistance
The other end of R8 is grounded, and the collector of NPN triode V1 is connected to the second voltage source+Vcc；
For direct current signal, since the equivalent impedance of the 4th capacitor C4 is infinitely great, biasing driving impedance is equivalent to the 6th electricity
Hinder R6；As frequency increases, biasing driving impedance reduces gradually, until being equivalent to the parallel connection of the 6th resistance R6, the 7th resistance R7
Value.It can be seen that circuit biased electrical resistance value varying with frequency and reduce, current drive capability increase, NPN triode V1's
Output current capacity is also consequently increased.When overshoot occurs for output voltage, biasing accelerates the output of control circuit energy sensing feed-back
The voltage change at end accelerates feedback control loop response speed, prevents output over control, and realize rapid overpressure defencive function.
Correlation based on the high-performance programme-controlled dc power that a output voltage/electric current that the present invention designs is 60V/8.5A
Performance indicator is as shown in the table.
As can be seen from the above table, not only voltage and current and its in terms of realize high-precision feedback control function
Can, the load effect of constant voltage/constant current is down to 0.3mV/0.2mA hereinafter, its voltage rise/fall time lower than 1mS is even more to have
There is incomparable transient response superiority, illustrates circuit output voltage feedback control capability with higher and good voltage wink
Become response regulation ability, reaches the design object of the invention patent.
Certainly, the above description is not a limitation of the present invention, and the present invention is also not limited to the example above, this technology neck
The variations, modifications, additions or substitutions that the technical staff in domain is made within the essential scope of the present invention also should belong to of the invention
Protection scope.
Claims (5)
1. a kind of Voltage Feedback control circuit, it is characterised in that: including voltage sample circuit, automatic gain amplifying circuit, isolation
Transmission control circuit and biasing accelerate control circuit；
Voltage sample circuit is configurable for being acquired output voltage, and collected output voltage is output to certainly
Dynamic gain amplifying circuit；
Automatic gain amplifying circuit is configurable for adjusting the transfer ratio of isolation control transmission circuit, and then adjusting pulsewidth tune
The duty ratio of device processed；
Transmission control circuit is isolated, is configurable for the primary of driving isolation and transmission circuit, controls the pulse of pulse width modulator
Width；
Biasing accelerates control circuit, is configurable for the voltage fluctuation of feedback output end, realizes rapid overpressure defencive function.
2. Voltage Feedback control circuit according to claim 1, it is characterised in that: voltage sample circuit, including the first electricity
Resistance, second resistance, 3rd resistor, the 4th resistance, first capacitor and first voltage source Vout+；One end of first resistor is connected to
One voltage source Vout+, one end composition common end of the other end of first resistor and second resistance is connected to one end of the 4th resistance,
The other end of 4th resistance is connected with one end of first capacitor, and the other end of second resistance and one end composition of 3rd resistor are public
End is connected to the other end of first capacitor, the other end ground connection of 3rd resistor.
3. Voltage Feedback control circuit according to claim 1, it is characterised in that: biasing acceleration control circuit, including the
Six resistance, the 7th resistance, the 8th resistance, the 4th capacitor, NPN triode and the second voltage source+Vcc；One end of 6th resistance and
One end composition common end of 7th resistance is connected to one end of the 4th resistance, and the other end of the 7th resistance is connected to the 4th capacitor
One end composition common end of one end, the other end of the 4th capacitor, the other end of the 6th resistance and the 8th resistance is connected to tri- pole NPN
The base stage of pipe, the other end ground connection of the 8th resistance, the collector of NPN triode are connected to the second voltage source+Vcc.
4. Voltage Feedback control circuit according to claim 1, it is characterised in that: automatic gain amplifying circuit, including the
Five resistance, the tenth resistance, the second capacitor, third capacitor, operational amplifier and reference voltage Vref；One end of tenth resistance and
One end composition common end of two capacitors is connected to the other end of first capacitor, and the other end of the tenth resistance is connected to operational amplifier
Inverting input terminal；The other end of second capacitor and one end composition common end of third capacitor are connected to one end of the 5th resistance,
The other end of the other end of third capacitor and the 5th resistance composition common end is connected to the output end of operational amplifier, operation amplifier
The non-inverting input terminal of device is connected to reference voltage Vref.
5. Voltage Feedback control circuit according to claim 1, it is characterised in that: isolation and transmission circuit, including the 9th electricity
Resistance and photoelectrical coupler；One end of 9th resistance is connected to the emitter of NPN triode, and the other end of the 9th resistance is connected to light
The first input end of electric coupler, the second input terminal of photoelectrical coupler are connected to the output end of operational amplifier, photoelectric coupling
First output end of device is connected to pulse width modulator, the second output terminal ground connection of photoelectrical coupler.
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201811492395.6A CN109765955B (en) | 2018-12-07 | 2018-12-07 | Voltage feedback control circuit |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201811492395.6A CN109765955B (en) | 2018-12-07 | 2018-12-07 | Voltage feedback control circuit |
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| CN109765955A true CN109765955A (en) | 2019-05-17 |
| CN109765955B CN109765955B (en) | 2020-10-09 |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN110971111A (en) * | 2019-11-14 | 2020-04-07 | 中电科仪器仪表(安徽)有限公司 | Pulse width modulator auxiliary power supply circuit |
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| CN108388299A (en) * | 2018-02-12 | 2018-08-10 | 上海集成电路研发中心有限公司 | Low pressure difference linear voltage regulator |
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|---|---|---|---|---|
| CN1734916A (en) * | 2004-08-11 | 2006-02-15 | 张真正 | Switch power supply circuit with output short circuit protection function |
| US20090122581A1 (en) * | 2006-12-22 | 2009-05-14 | Sanken Electric Co., Ltd | Alternating current power supply device and integrated circuit for alternating current power supply device |
| US20100277959A1 (en) * | 2009-04-30 | 2010-11-04 | Hong Fu Jin Precision Industry (Shenzhen) Co., Ltd. | Power supply module |
| CN202513827U (en) * | 2012-04-16 | 2012-10-31 | 唐山电动车研发与检测有限公司 | Non-overshoot voltage-stabilizing switching power supply |
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| CN109765955B (en) | 2020-10-09 |
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Address after: 233010 no.1300, Yinghe Road, Yuhui District, Bengbu City, Anhui Province Patentee after: CLP kesiyi Technology (Anhui) Co.,Ltd. Address before: 233010 no.1300, Yinghe Road, Yuhui District, Bengbu City, Anhui Province Patentee before: CETC INSTRUMENTATION (ANHUI) Co.,Ltd. |