CN203983996U - A kind of circuit of power factor correction - Google Patents
A kind of circuit of power factor correction Download PDFInfo
- Publication number
- CN203983996U CN203983996U CN201420353647.8U CN201420353647U CN203983996U CN 203983996 U CN203983996 U CN 203983996U CN 201420353647 U CN201420353647 U CN 201420353647U CN 203983996 U CN203983996 U CN 203983996U
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- circuit
- switch element
- power factor
- factor correction
- winding
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- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
- Y02E40/00—Technologies for an efficient electrical power generation, transmission or distribution
- Y02E40/30—Reactive power compensation
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- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
- Y02E40/00—Technologies for an efficient electrical power generation, transmission or distribution
- Y02E40/40—Arrangements for reducing harmonics
Abstract
The utility model relates to a kind of circuit of power factor correction (PFC), comprise main circuit and drive circuit, described main circuit comprises an inductance element, first switch element, with a diode, described inductance element comprises a main winding, described main winding is connected with described diode with described the first switch element, when the first switch element turn-offs, described main winding discharges energy storage by described diode, described inductance element also comprises that drives a winding, the induced voltage signal that described drive circuit produces according to described driving winding drives described the first switch element, and control the ON time of described the first switch element.The utility model has substituted the control chip of PFC with the control circuit that discrete component forms, reduced cost.This pfc circuit scheme is widely used simultaneously, not only can be applied in booster circuit, but also can be applied in the circuit topology of the multiple non-isolation such as reduction voltage circuit and buck.
Description
Technical field
The utility model relates to a kind of circuit, especially relates to a kind of circuit of power factor correction.
Background technology
In order to control the humorous wave interference of Electrical and Electronic equipment to power supply grid, the limitation standard of controlling particular device transmitting harmonic current has all been formulated in many countries and regions, as IEC61000-3-2, and GB GB17625 etc.In order to meet the regulation of these regulations, many power supplys, Switching Power Supply particularly, when meeting certain condition, as for illumination, in input active power, be greater than 25W, all can add APFC, realize line current and follow line change in voltage, line current higher harmonic content is eased down in standard limited range.
Fig. 1 is the conventional at present switch power supply system block diagram with circuit of power factor correction.In Fig. 1, switch power supply system comprises, insurance EMI filter unit, rectifier bridge, differential mode filtering and power factor correction (PFC) main circuit.Insurance EMI filter unit is connected with civil power input, and in insurance EMI filter unit, the Main Function of insurance is while avoiding subsequent conditioning circuit to be short-circuited fault, to affect electrical network normally to work, and avoids subsequent conditioning circuit to have an accident simultaneously; EMI filtering is mainly anti-lightning surge and eliminates differential mode and common mode electromagnetic interference.Rectifier bridge is comprised of four high-voltage diodes conventionally, and input exchange signal is converted into direct current signal.Differential mode filtering is further carried out filtering the high frequency differential mode signal of Switching Power Supply below, suppresses the harmonic effects to electrical network.PFC main circuit, after differential mode filtering, is used for realizing input current and follows input voltage variation, controls output voltage V o simultaneously, and provides certain power to load.
PFC main circuit can be applied multiple circuit topological structure, and as booster circuit, reduction voltage circuit, step-up/step-down circuit, circuit of reversed excitation, half-bridge circuit and full-bridge circuit etc., circuit topology is selected according to different capacity and input-output characteristic.Fig. 2 is the schematic diagram of booster circuit, comprises input inductance L, the first switch element S, output diode D and output filter capacitor C.The first switch element S can be pliotron, also can be field effect transistor, general work state be divided into cut-off and saturation conduction, the first switch element S when normal work in high frequency, high frequency switches cut-off and two states of saturation conduction: when switch S saturation conduction, and the energy storage of input inductance L; When switch S disconnects, inductance L releases energy to output by diode D.High frequency output electric current after capacitor C, provides low ripple DC signal output after filtering.
But existing circuit of power factor correction PFC is generally used the circuit mode of the additional field effect transistor of control chip to realize, and cost compare is high.
Summary of the invention
The technical problems to be solved in the utility model is to provide a kind of circuit of power factor correction cheaply, when realizing Harmonics of Input control, limits output voltage range.
For achieving the above object, the utility model provides a kind of circuit of power factor correction, comprising: main circuit and drive circuit, and described main circuit comprises an inductance element, first switch element, and a diode; Described inductance element comprises a main winding, and described main winding is connected with described diode with described the first switch element, and when the first switch element turn-offs, described main winding discharges energy storage by described diode; It is characterized in that, described inductance element also comprises that drives a winding, and the induced voltage signal that described drive circuit produces according to described driving winding drives described the first switch element, and controls the ON time of described the first switch element.
Preferably, circuit of power factor correction also comprises a control circuit and a second switch element, and described second switch element is connected with the control end of described the first switch element, and described control circuit is controlled the ON time of described second switch element.
Preferably, control circuit comprises an output feedback circuit, described output feedback circuit is connected with the output of described main circuit, and when the output voltage of described main circuit is greater than predetermined threshold value, described output feedback circuit is controlled the described second switch element conductive time.
Preferably, described output feedback circuit is resistor voltage divider circuit or optical coupling isolation circuit.
Preferably, circuit of power factor correction also comprises an impedance component, and described impedance component is connected with described the first switch element, according to the electric current of described the first switch element of flowing through, generates feedback voltage.
Preferably, above-mentioned control circuit comprises a compensating circuit, and described compensating circuit is controlled the ON time of described second switch element according to the superposition value of the induced voltage of described driving winding and described feedback voltage.
Preferably, described impedance component is resistance or Current Mutual Inductance circuit.
Preferably, above-mentioned circuit of power factor correction also comprises an electric capacity, described electric capacity and described driving windings in series.
The main circuit of above-mentioned circuit of power factor correction is booster circuit or reduction voltage circuit or lifting circuit.
Compared with prior art, circuit of power factor correction of the present utility model has adopted discrete component to form the mode of the additional switch of control circuit, compares with use PFC control chip mode, has reduced cost.The scope of this technical scheme application is wider simultaneously, not only can be applied in booster circuit, but also can be applied in the circuit topology of the multiple non-isolation such as reduction voltage circuit and buck.
According to below with reference to accompanying drawing to description of the present utility model, other targets of the present utility model and effectiveness will become apparent, and reader can fully understand the utility model.
Accompanying drawing explanation
Fig. 1 is the Switching Power Supply structural representation of prior art;
Fig. 2 is the schematic diagram of booster circuit;
Fig. 3 is the circuit diagram of the embodiment mono-of the utility model circuit of power factor correction;
Fig. 4 is a kind of schematic diagram of execution mode of control circuit of the embodiment bis-of the utility model circuit of power factor correction;
Fig. 5 is the schematic diagram of another kind of execution mode of control circuit of the embodiment bis-of the utility model circuit of power factor correction;
Fig. 6 is the schematic diagram of another kind of execution mode of control circuit of the embodiment bis-of the utility model circuit of power factor correction;
Fig. 7 is the circuit diagram of the embodiment tri-of the utility model circuit of power factor correction;
Fig. 8 is the circuit diagram of the embodiment tetra-of the utility model circuit of power factor correction.
In above-mentioned accompanying drawing, same reference numerals identical, the similar or corresponding element of indication or function.
embodiment
Below with reference to graphic, by embodiment, describe specific embodiment of the utility model in detail.
Embodiment mono-:
Referring to Fig. 3, this figure is the schematic diagram of the embodiment mono-of the utility model circuit of power factor correction.
Circuit of power factor correction in the utility model embodiment (pfc circuit) 30 comprises the part that in main circuit 300(Fig. 3, dotted line frame surrounds) and drive circuit 301.Wherein main circuit 300 comprises, inductance component L, the first switch element S and diode D.Inductance component L comprises main winding L1 and drives winding L 2.Main winding L1 connects with the first switch element S, and diode D is connected on the tie point of main winding L1 and the first switch element S.In the circuit of power factor correction 30 of Fig. 3, also comprise impedance component R, impedance component R is connected on the first switch element S below.Input voltage vin is added in the circuit two ends of main winding L1, the first switch element S and impedance component R series connection.What main circuit 300 adopted is booster circuit, but is also to adopt step-down and step-up/step-down circuit.In Fig. 3, inductance component L is an inductance, by increasing a winding as driving winding L 2 on inductance, this drives winding L 2 to connect with drive circuit 301, drives the induced voltage at winding L 2 two ends by drive circuit 301, to control the ON time of the first switch element S.Stain in Fig. 3 is two winding L 1 of inductance component L, the Same Name of Ends of L2, and Same Name of Ends lays respectively at relative one end of two winding L 1, L2.In embodiment mono-, this drives winding L 2 one end ground connection, and the other end is connected to the control end of the first switch element S by drive circuit 301, and now driving voltage equals to drive the induced voltage of winding.The first switch element S can be pliotron or field effect transistor, if the first switch element S is pliotron, control end is base stage; If the first switch element S is field effect transistor, control end is gate pole.Drive circuit 301 can be the combination of resistance, electric capacity or resistance and electric capacity, and drive circuit 301 can impact be added in the voltage current waveform of the first switch element S control end, thereby controls the ON time of the first switch element S.The impedance component R of the first switch element S below series connection can be resistance, or Current Mutual Inductance circuit, and this impedance component R is mainly that feedback flow is through the current signal of the first switch element S, for effects such as overcurrent protection or auxiliary the first switch element S shutoffs.After the first switch element S saturation conduction, drive winding L 2 Same Name of Ends for just, by meeting impedance component R under drive circuit 301 and the first switch element S, provide the first switch element S control end signal, and determine the first switch element S ON time, within this time, the main winding L1 electric current of inductance component L is linear to rise; After the first switch element S disconnects, the main winding L1 of inductance component L releases energy to output by diode D, after filtering after capacitor C, low ripple DC signal output is provided, the linear decline of electric current of inductance component L, drives winding L 2 Same Name of Ends for negative, only has after the electric current of inductance component L drops to zero, drive winding L 2 to reset, drive circuit 301 provides the conducting again of activated with energy switch S.By above-mentioned pfc circuit, realize input current and followed input voltage variation, controlled electric current higher harmonic content, limit output voltage range simultaneously.
Embodiment bis-
Below in conjunction with Fig. 4, Fig. 5 and Fig. 6, the embodiment bis-of the utility model circuit of power factor correction 40,50,60 is described.
The circuit of power factor correction 40 of embodiment bis-is compared with embodiment mono-, has increased the part of dotted line in a control circuit 400(Fig. 6), and a second switch element S1.Described second switch element S1 is connected with the control end of described the first switch element S, and control circuit 400 is controlled the ON time of second switch element S1.
Fig. 4 shows the circuit diagram of the 400 1 kinds of execution modes of control circuit that meet the utility model pfc circuit 40.Referring to Fig. 4, control circuit is an output feedback circuit 402, and output feedback circuit 402 is connected with the output of pfc circuit 40.This output comprises a diode D and filter capacitor C, and output feedback circuit 402 is connected with diode D.Second switch element S1 is connected between the control end and ground of the first switch element S, and second switch element S1 can be triode or field effect transistor, and the control end of second switch element S1 is to be controlled by output feedback circuit 402.Output feedback circuit 402 can be realized with resistor voltage divider circuit, or by optical coupling isolation circuit, isolates feedback and realize.When the output voltage of circuit of power factor correction 40 surpasses while presetting threshold value, second switch element S1 conducting, drags down the control signal of the first switch element S, makes the first switch element switch S shutoff; When output voltage is during lower than setting threshold, second switch element S1 disconnects, and does not affect the control end voltage of the first switch element S.Like this, output feedback circuit 402 and second switch element S1 realize the function of an output over-voltage protection.When realizing Harmonics of Input control, limit output voltage range, avoid the design to subsequent conditioning circuit to bring adverse effect, even damage device.
Fig. 5 is the circuit diagram of another kind of execution mode that meets the control circuit of the utility model pfc circuit 50 in embodiment bis-
In Fig. 5, control circuit is a compensating circuit 503, and the effect of compensating circuit 503 is to realize input feedfoward control.When input voltage raises, suitably reduce the ON time of the first switch element S, make the output voltage can too fast change is not large because of the rising of input voltage.Compensating circuit 503 needs the current signal that gathers driving winding L 2 Same Name of Ends voltages and the first switch element S as feedback.Drive winding L 2 Same Name of Ends voltages to be proportional to input voltage, by input voltage, through certain turn ratio conversion, come, this is because be added in the voltage input voltage just of the main winding L1 of inductance component L when the first switch element S conducting.And the current signal of the first switch element S that flows through is undertaken after impedance transformation by impedance component R, become feedback voltage signal and be superimposed upon compensating circuit.Drive winding L 2 Same Name of Ends signals and above-mentioned feedback voltage by linear superposition or Nonlinear Superposition, after arriving predetermined threshold value, make second switch element S1 conducting, thereby turn-off the first switch element S, so just can realize input feedfoward control, threshold value can be set to 1V to 5V, in embodiment tetra-, setting threshold is 5V.By compensating circuit 503, utilize the ON time of controlling second switch element S1, control the shutoff ON time of the first switch element S.When realizing Harmonics of Input control, limit output voltage range.
In addition, the control circuit 400 that meets the utility model pfc circuit 40 also can comprise output feedback circuit 402 and compensating circuit 503 simultaneously, as shown in Figure 6.Control circuit 400 is realized the control to second switch element S1 ON time by output feedback circuit or compensating circuit.
In above embodiment, can drive above winding L 2, or driving the capacitor C 1 of connecting below winding L 2, if C1 is placed on, drive between winding L 2 and ground, can also be as an auxiliary power supply effect in circuit.Increase series capacitance C1, can raise total driving voltage, because driving voltage equals to drive winding L 2 voltages and capacitor C 1 voltage sum above, raise driving voltage and can guarantee that the first switch element S can correct conducting after inductive current zero passage, particularly when input voltage and output voltage relatively approach.Meanwhile, capacitor C 1 voltage above also participates in compensating circuit 503 the insides, can Optimization Compensation characteristic, and output voltage stability is improved.
Embodiment tri-
Referring to Fig. 7, this figure is the schematic diagram of the utility model circuit of power factor correction 70 embodiment tri-
With reference to Fig. 7, circuit of power factor correction comprises main circuit, drive circuit, compensating circuit and output feedback circuit, second switch element S1, and wherein main circuit comprises inductance component L, the first switch element S, diode D, inductance component L comprises main winding L1 and drives winding L 2; Drive circuit is by driving resistance R d, driving capacitor C d to be in series; Compensating circuit 503 consists of resistance R c1, Rc2, capacitor C c, diode Dc1 and voltage-stabiliser tube Vz1; Output feedback circuit comprises resistance R o1, Ro2, diode Dc2 and voltage-stabiliser tube Vz2.The first switch element S adopts pliotron, pliotron S below series resistance Rs ground connection, and Rs plays electric current sampling action.Electric current is connected to the base stage of S through resistance R start from output, driving winding L 2 and inductance L coupling, and one end is by capacitor C 1 ground connection, and one end is connected to the base stage of S through overdrive resistance R d and driving capacitor C d in addition; Diode D1 and D2 play reverse afterflow when switch S disconnects; Second switch element S1 is small-signal triode, for turn-offing the first switch element S.The control signal of second switch element S1 is from two aspects, one is to drive the driving voltage of winding induction through the superposed signal of resistance R c1 and the process capacitor C c of the voltage above sampling resistor Rs and resistance R c2, another one is output voltage through resistance R o1 and resistance R o2 dividing potential drop feedback signal, and these two signals are added to respectively the base stage of second switch element S1 by diode Dc1 and voltage-stabiliser tube Vz1 and diode Dc2 and voltage-stabiliser tube Vz2.
Concrete operation principle is as follows: the startup of pfc circuit realizes by resistance R start, after powering on, output voltage provides base current to the first switch element S through Rstart, after the first switch element S conducting, input voltage is added to above inductance L, according to Same Name of Ends, drive winding L 2 to induce just lower negative voltage above, by resistance R d and capacitor C d, further strengthen the conducting of the first switch element S, make the first switch element S saturated rapidly, the linear rising of electric current of inductance L produces the linear voltage signal rising on resistance R s.The shutoff of the first switch element S is subject to the impact of several aspects below: 1) drive current declines gradually after resistance R d and capacitor C d, simultaneously because the voltage linear above resistance R s rises, finally make to flow into the first switch element S base current reverse, in extraction base stage, cross after multi-charge, the first switch element S enters off-phases; 2) driving voltage superposes through Cc and Rc2 through overvoltage Rc1 and the voltage above resistance R s, after surpassing voltage-stabiliser tube Vz1 and diode Dc1 conduction voltage drop, make second switch element S1 base stage start conducting, the first switch element S base charge is injected in collector electrode shunting by second switch element S1, the shutoff of acceleration switch the first switch element S, this is also the result of input voltage feed forward control effect; 3) output voltage is after resistance R o1 and resistance R o2 dividing potential drop, if surpass voltage-stabiliser tube Vz2 and diode Dc2 conduction voltage drop, also can make second switch element S1 base stage start conducting, finally make the first switch element S turn-off, this shutoff effect is mainly restriction maximum output voltage.When closing, the first switch element S has no progeny, the linear decline of electric current of inductance component L, the voltage being added in above inductance component L is that output voltage deducts input voltage, drive winding L 2 sense negative under just, now capacitor C d and C1 reset by diode D1 and D2. etc. after inductance component L electric current drops to zero, now drive winding L 2 both end voltage also to drop to zero, driving voltage equals capacitor C 1 voltage above, triggers the first switch element S restart by resistance R d and capacitor C d.Above pfc circuit, when realizing Harmonics of Input control, also limits output voltage range.
In the above embodiment of the utility model, the main circuit of circuit of power factor correction adopts the topological structure of booster circuit, and main circuit can also be extended to reduction voltage circuit and step-up/step-down circuit.
Embodiment tetra-
Referring to Fig. 8, Fig. 8 is the circuit diagram of the utility model circuit of power factor correction embodiment tetra-.In the present embodiment, circuit of power factor correction comprise a main circuit 800 and drive back 801. wherein main circuit be a step-up/step-down circuit being formed by the first switch element S, inductance component L and diode D.The driving winding L 2(unlabelled of inductance component L) by drive circuit 801, control the ON time of the first switch element S.
Above-described embodiment is exemplary, and does not wish that they limit technical method of the present utility model.Although describe the utility model in detail with reference to preferred embodiment; but be understood by those skilled in the art that; can be in the situation that do not depart from the spirit of the utility model technical method and category and revise or be equal to and replace technical method of the present utility model, these modifications and be equal to the protection category that replacement also belongs to the utility model claims.
Claims (10)
1. a circuit of power factor correction, comprises main circuit (300) and drive circuit (301,401,501,601,801), and described main circuit comprises an inductance element (L), first switch element (S), and a diode (D); Described inductance element (L) comprises a main winding (L1), described main winding (L1) is connected with described diode (D) with described the first switch element (S), when the first switch element (S) turn-offs, described main winding (L1) discharges energy storage by described diode (D); It is characterized in that, described inductance element also comprises that drives a winding (L2), the induced voltage signal that described drive circuit (301,401,501,601,801) produces according to described driving winding (L2) drives described the first switch element (S), and controls the ON time of described the first switch element (S).
2. circuit of power factor correction according to claim 1, it is characterized in that, also comprise a control circuit (400) and a second switch element (S1), described second switch element (S1) is connected with the control end of described the first switch element (S), and described control circuit (400) is controlled the ON time of described second switch element (S1).
3. circuit of power factor correction according to claim 2, it is characterized in that, described control circuit comprises an output feedback circuit (402), described output feedback circuit is connected with the output of described main circuit (300), when the output voltage of described main circuit is greater than predetermined threshold value, described output feedback circuit (402) is controlled described second switch element (S1) ON time.
4. circuit of power factor correction according to claim 3, is characterized in that, described output feedback circuit (402) is resistor voltage divider circuit or optical coupling isolation circuit.
5. circuit of power factor correction according to claim 2, it is characterized in that, also comprise an impedance component (R), described impedance component (R) is connected with described the first switch element (S), according to the electric current of described the first switch element (S) of flowing through, generates feedback voltage.
6. circuit of power factor correction according to claim 5, it is characterized in that, described control circuit comprises a compensating circuit (503), and described compensating circuit (503) is controlled the ON time of described second switch element (S1) according to the superposition value of the induced voltage of described driving winding (L2) and described feedback voltage.
7. circuit of power factor correction according to claim 5, is characterized in that, described impedance component is resistance or Current Mutual Inductance circuit.
8. according to the arbitrary described circuit of power factor correction of claim 1 to 7, it is characterized in that, also comprise an electric capacity (C1), described electric capacity (C1) is connected with described driving winding (L2).
9. according to the arbitrary described circuit of power factor correction of claim 1 to 7, it is characterized in that, described main circuit is booster circuit or reduction voltage circuit or lifting circuit.
10. according to the arbitrary described circuit of power factor correction of claim 1 to 7, it is characterized in that, described the first switch element (S) and/or second switch element (S1) are triode or field effect transistor.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201420353647.8U CN203983996U (en) | 2014-06-30 | 2014-06-30 | A kind of circuit of power factor correction |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201420353647.8U CN203983996U (en) | 2014-06-30 | 2014-06-30 | A kind of circuit of power factor correction |
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| Publication Number | Publication Date |
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| CN203983996U true CN203983996U (en) | 2014-12-03 |
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| CN201420353647.8U Expired - Fee Related CN203983996U (en) | 2014-06-30 | 2014-06-30 | A kind of circuit of power factor correction |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN105305455A (en) * | 2014-06-30 | 2016-02-03 | 欧普照明股份有限公司 | Power factor correction circuit (PFC) |
-
2014
- 2014-06-30 CN CN201420353647.8U patent/CN203983996U/en not_active Expired - Fee Related
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN105305455A (en) * | 2014-06-30 | 2016-02-03 | 欧普照明股份有限公司 | Power factor correction circuit (PFC) |
| CN105305455B (en) * | 2014-06-30 | 2019-11-22 | 欧普照明股份有限公司 | A kind of circuit of power factor correction |
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