CN201199672Y - Flyback converting device with single-stage power factor calibrating circuit - Google Patents

Abstract

The utility model discloses a flyback type switching device with a single stage power factor correcting circuit, which comprises a first rectifier for commutating input alternating-current voltage to generate first full wave direct current voltage; an energy storage capacitor for filtering the first full wave direct current voltage; a second rectifier for commutating input alternating-current voltage to generate second full wave direct current voltage; an energy storage inductor for carrying out energy storage to the second full wave direct current voltage; a change-over switch and a transformer with a primary winding and a coupled winding. The voltage of the energy storage capacitor can be restrained by connecting the coupled winding of one transformer in a PFC inductive current loop in series. A part of energy in the energy storage capacitor and the coupled winding is transmitted to a secondary winding by the primary winding of the transformer, and the other part charges up the energy storage capacitor, thereby reducing the leakage inductance loss caused by the coupled winding, reducing the spike voltage and the switching loss generated by the change-over switch after being closed, and further improving the whole efficiency of the transformer.

Description

Flyback conversion equipment with single-stage power factor correction circuit

Technical field

The utility model relates to field of power electronics, relates in particular to a kind of flyback conversion equipment with single-stage power factor correction circuit.

Background technology

The extensive at present traditional often two-stage type power factor correcting technology of power factor correction circuit that adopts, its circuit unit is many, and cost is higher, and the circuit complexity, is not suitable for the middle low power occasion.For reducing the cost of two stage power factor correction circuit, people have proposed multiple single-stage power factor correcting technology in recent years.General single-stage power factor correction circuit is to work in discontinuous conduction mode by the control inductive current, realizes the power factor correcting function automatically.In order to realize the balance of input and output power, guarantee the retention time of power supply simultaneously, need a low frequency electric capacity storage power.Because input current is discontinuous, contains a large amount of Harmonics of Input, so need add electromagnetic interference suppression circuit at input, entire circuit is with regard to more complicated.

In the power factor correction circuit of single-stage,, realize the quick adjustment of correction, electrical isolation and the output voltage of input current waveform simultaneously by single control circuit.Owing to removed in traditional two-step way control, when stating function in realization, must guarantee storage capacitor voltage (usually below 400V) within suitable scope to storage capacitor voltage.Most single-level circuit is by an importation that is similar to stepup transformer (Booster), and the DC/DC of forward converter (Forward Converter) or flyback converter (Flyback Converter) partly forms.Usually, the characteristic of single-level circuit aspect power factor and total harmonic distortion is not as two-stage circuit.Usually (Power Factor, PF) 0.8～0.95, total harmonic distortion (THD) is within 20～75% scope for power factor.

As shown in Figure 1, it is the denomination of invention " AC/DCFlyback Converter " that M.M.Jonanovic and L.Huber apply for, the patent No. is U.S.Pat.No.6,950,319 United States Patent (USP), this patent have proposed a kind of simple, low-cost, high efficiency and the good flyback conversion equipment 100 with single-stage power factor correction circuit of output characteristic.In Fig. 1, insert an energy-storage reactor LPFC between the elementary winding N1 of two rectifier diode D3, D4 and transformer Tr, the N2 centre tap, the corrective action that realizes input current Ii by EMI filter circuit 110.And, two rectifier diode D1, D2 in addition are by EMI filter circuit 110, the electric voltage dropping that is implemented in energy storage capacitor C1 constitutes the direct charge circuit of input voltage vin to energy storage capacitor C1, and can reduce the ripple of input current Ii when being lower than input voltage vin.The elementary winding N1 of energy-storage reactor LPFC and rectifier diode D3, D4 and transformer Tr, N2 centre tap are connected in series, can be the voltage limit of energy storage capacitor C1 in certain scope.For the input voltage vin of scope between 90～264Vrms, the voltage of energy storage capacitor C1 can maintain below the 400V usually.

Again with reference to figure 1, when diverter switch Q1 conducting (turn on) time, elementary winding N2 and the energy-storage reactor LPFC of transformer Tr are in series, at this moment, elementary winding N2 can feedback energy storage capacitor C1 voltage, reducing the rate of rise of energy-storage reactor LPFC electric current, and then suppress the magnitude of voltage of energy storage capacitor C1.In addition, when diverter switch Q1 disconnects (turn off), elementary winding N1 and the energy-storage reactor LPFC of transformer Tr are in series, elementary winding N1 is to the reflected voltage of transformer Tr primary side output, can increase the descending slope of energy storage inductor LPFC electric current, and then suppress the magnitude of voltage of energy storage capacitor C1.So no matter diverter switch Q1 is conducting or ends, can suppress the magnitude of voltage of energy storage capacitor C1 by the induced voltage of the elementary winding N1 of transformer Tr, N2.

With reference to figure 1, when diverter switch Q1 conducting, input voltage vin can increase the excitatory energy of transformer Tr by elementary winding N2 again.When diverter switch Q1 by the time, stored energy among the energy-storage reactor LPFC, directly to the transmission of transformer Tr primary side, these can promote the efficient of whole converter by elementary winding N1.The ratio of the elementary winding N1 of optimization, N2 can be improved the performance of whole converter, and pointers such as power factor, storage capacitor voltage and efficient are carried out optimization.

With reference to figure 1, the flyback conversion equipment 100 that wherein has the single-stage power factor correction circuit can be operated in the input range of full voltage well, simultaneously again, improve later single stage topology, and reduced the number of series diode in the loop,, promoted efficient to reduce conduction loss.But in the time of diverter switch Q1 conducting, the electric current of the electric current of energy-storage reactor LPFC and elementary winding N1 all flows through elementary winding N2, thereby causes big electric current.And after diverter switch Q1 disconnects, flow through the big electric current of elementary winding N2, will cause very big peak voltage letting out between extreme and the source terminal of diverter switch Q1, thereby increase the switching loss of diverter switch Q1.

The utility model content

In order to reduce the whole efficiency of conduction loss, raising converter, the utility model provides a kind of flyback conversion equipment with single-stage power factor correction circuit, includes one first rectifier, an energy storage capacitor, one second rectifier, an energy-storage reactor, a switching switch and a transformer.Wherein, first rectifier carries out rectification to an input ac voltage, to produce one first full-wave direct current voltage.Energy storage capacitor is coupled between first rectifier and the earth terminal, and the first full-wave direct current voltage is carried out filtering.Second rectifier carries out rectification to input ac voltage, to produce one second full-wave direct current voltage.Energy-storage reactor is coupled to second rectifier, and the second full-wave direct current voltage is carried out energy storage.Diverter switch is coupled to earth terminal.Transformer has an elementary winding, secondary winding and a coupling winding, wherein elementary winding and diverter switch coupled in parallel are in energy storage capacitor, and coupling winding and diverter switch coupled in series are in energy-storage reactor, and secondary winding then is coupled to an output capacitance by a rectifier diode.

This rectifier diode is a Schottky diode or a synchronous diode.

This flyback conversion equipment with single-stage power factor correction circuit also comprises a controller, and this controller is coupled to this output storage capacitor, and this controller receives the output voltage on this output storage capacitor, and controls this diverter switch.

This first rectifier is at this input ac voltage during greater than the voltage on this energy storage capacitor, exports this first full-wave direct current voltage with to this energy storage capacitor charging.

Be connected with a public rectifier diode between this first rectifier and this second rectifier.

This flyback conversion equipment with single-stage power factor correction circuit also comprises one first clamper, and this first clamper is coupled to this diverter switch.

This first clamper comprise one first forward diode be coupled to the capacitance-type resistor group of a parallel connection.

This flyback conversion equipment with single-stage power factor correction circuit also comprises one second clamper, and this second clamper is coupled to this second rectifier.

This second clamper comprise one second forward diode be coupled to this capacitance-type resistor group in parallel.

Compared with prior art, the utlity model has following beneficial effect:

Flyback conversion equipment of the present utility model has high power factor, low conduction loss and high efficiency advantage, and the utility model suppresses the voltage of energy storage capacitor by the coupling winding of a transformer of series connection in the loop of PFC inductive current.Simultaneously, energy in energy-storage reactor and the coupling winding, a part will be transmitted to secondary winding through the elementary winding of transformer, another part will charge to energy storage capacitor, to reduce the caused leakage inductance loss of coupling winding, and after reducing diverter switch and ending, peak voltage that is produced and switching loss, and then promote the efficient of converter integral body.

Description of drawings

Fig. 1 is the existing apparatus circuit diagram;

Fig. 2 is the device circuit schematic diagram of the utility model first embodiment;

Fig. 3 A to Fig. 3 D is a circuit operation schematic diagram of the present utility model;

Fig. 4 is an operation waveform schematic diagram of the present utility model;

Fig. 5 is the device circuit schematic diagram of the utility model second embodiment; And

Fig. 6 is the device circuit schematic diagram of the utility model the 3rd embodiment.

Wherein,

Prior art:

Flyback conversion equipment 100

EMI filter circuit 110

Input voltage vin

Input current Ii

Diode D1～D7

Energy storage capacitor C1

Output capacitance C2

Energy-storage reactor LPFC

Transformer Tr

Winding N1, N2, N3

Earth terminal G

Diverter switch Q1

The utility model:

Flyback conversion equipment 200,300,400

First rectifier 201

Energy storage capacitor C1

Second rectifier 202

Energy-storage reactor LPFC

Diverter switch Q1

Transformer Tr

EMI filter circuit 210

Rectifier diode D1～D7

Input voltage vin

Output capacitance C2

Elementary winding N1

Coupling winding N2

Secondary winding N3

Earth terminal G

Diverter switch Q1

Controller 204

The first full-wave direct current voltage V1

The second full-wave direct current voltage V2

Control signal SW

Forward diode D8, D9, D10

Resistance R 1, R2

Capacitor C 3

Output voltage VO

Embodiment

Please refer to Fig. 2, be the device circuit schematic diagram of the utility model first embodiment.Flyback conversion equipment 200 with single-stage power factor correction circuit of the present utility model includes one first rectifier 201, an energy storage capacitor C1, one second rectifier 202, an energy-storage reactor LPFC, a switching switch Q1 and a transformer Tr.Wherein first rectifier 201 carries out rectification by 210 couples one input ac voltage Vin of an EMI filter circuit, to produce one first full-wave direct current voltage V1.Energy storage capacitor C1 then is coupled between first rectifier 201 and the earth terminal G, and the first full-wave direct current voltage V1 is carried out filtering.Wherein during greater than the voltage on the energy storage capacitor C1, rectification input ac voltage Vin is in order to produce the first full-wave direct current voltage V1 so that energy storage capacitor C1 is charged at input ac voltage Vin for this first rectifier 201.

In addition, second rectifier 202 equally also carries out rectification by 210 couples of input ac voltage Vin of EMI filter circuit, to produce one second full-wave direct current voltage V2.And energy-storage reactor LPFC is coupled to second rectifier 202, in order to the second full-wave direct current voltage V2 is carried out energy storage.Diverter switch Q1 then is coupled to an elementary winding N1 and the coupling winding N2 of earth terminal G and transformer Tr.Wherein, behind the elementary winding N1 and diverter switch Q1 coupled in series of transformer Tr, coupled in parallel is in energy storage capacitor C1 again, and the coupling winding N2 of transformer Tr and diverter switch Q1 coupled in series are in energy-storage reactor LPFC.

Again with reference to figure 2, first rectifier 201 includes rectifier diode D1, D2, D5 and D6, and second rectifier 202 includes rectifier diode D3, D4, D5 and D6, and wherein rectifier diode D5, D6 are public diode between first rectifier 201 and second rectifier 202.Simultaneously, transformer Tr also includes level winding N3 one time, and this secondary winding N3 sees through a rectifier diode D7 and is coupled to an output capacitance C2.In addition, flyback conversion equipment 200 further comprises a controller 204, and this controller 204 is coupled to output storage capacitor C2, according to the output voltage on this output capacitance C2, to export a control signal SW to control the switching cycle of this diverter switch Q1.

Again with reference to figure 2, flyback conversion equipment 200 has kept the advantage and the achievement of circuit among Fig. 1, but, in flyback conversion equipment 200 of the present utility model, the coupling winding N2 of transformer Tr is connected on the loop of energy-storage reactor LPFC, rather than in the image pattern 1, the centre tap of transformer primary is connected on the loop of energy-storage reactor LPFC.Controller 204 comes the conducting of control its switch Q1 by the detection to output voltage VO and ends, and its control mode can take to decide FREQUENCY CONTROL, and this moment, transformer Tr was operated in continuous conducting (CCM) or discontinuous conducting (DCM) pattern.In aforementioned, control mode also can be taked variable frequency control, and this moment, transformer Tr was operated in critical conduction mode (DCM/CCM), under this critical conduction mode (DCM/CCM), must the frequency of diverter switch Q1 be limited, to reduce the loss of the diverter switch Q1 under the underloading.Such as, can be by the restriction diverter switch Q1 mode of deadline.And the rectifier diode D7 of transformer Tr primary side can adopt Schottky diode (Schottky Diode) or synchronous diode.

Fig. 3 A to Fig. 3 D is a circuit operation schematic diagram of the present utility model.And Fig. 4 is an operation waveform schematic diagram of the present utility model.Cooperate Fig. 4, with reference to figure 3A and Fig. 3 B.In the utility model, the switch periods of diverter switch Q1 can be divided into four-stage a～d.

With reference to figure 3A and Fig. 3 B, at a in the stage, diverter switch Q1 conducting, energy storage capacitor C1 i.e. elementary winding N1 and the magnetizing inductance energy storage of diverter switch Q1 in transformer Tr by transformer Tr.Simultaneously, input ac voltage Vin by second rectifier 202, transformer Tr coupling winding N2 and diverter switch Q1 to energy-storage reactor LPFC energy storage.And, also pass through the magnetizing inductance energy storage of the coupling winding N2 of transformer Tr to transformer Tr inside.

That supposes AC power is input as formula (1)

v _in＝U _in?sin?ωt ...(1)

When diverter switch Q1 conducting, the current equation formula (2) of energy-storage reactor LPFC is:

$L_{\mathrm{PFC}}\frac{{\mathrm{di}}_{\mathrm{PFC}}}{\mathrm{dt}}=U_{\mathrm{in}}\left|\sin \mathrm{\&omega;t}\right|-\frac{N_2}{{\mathrm{<figure-callout\; id="1"\; label="N"\; filenames="Y200820111620E00161.png,Y200820111620E00162.png"\; state="\{\{state\}\}">N</figure-callout>}}_1}\&times;U_{\mathrm{CB}}...\left(2\right)$

The current equation formula of magnetizing inductance is (3)

$L_m\frac{{\mathrm{di}}_m}{\mathrm{dt}}=U_{\mathrm{CB}}...\left(3\right)$

Wherein, U _CBBe the voltage of energy storage capacitor C1, L _mBe the magnetizing inductance of transformer Tr, L _PFCBe the inductance value of energy-storage reactor LPFC, i _mBe the exciting curent of transformer Tr, i _PFCElectric current for energy-storage reactor LPFC.

Suppose that the electric current that flows out from energy storage capacitor C1 is i _CB, i _CBCan obtain by formula (4):

i _CB＝i _m+i _N1?...(4)

Wherein, i _N1Ideal current for elementary winding N1 among the transformer Tr.At this moment, coupling winding N2 only flows through the current i of energy-storage reactor LPFC _PFC, i _PFCValue can obtain by formula (5):

i _N2＝i _PFC?...(5)

According to the principle of ampere-turn equilibrium, draw formula (6)

N ₂×i _N2+N ₁×i _N1＝0 ...(6)

According to above two formulas (5), (6), promptly draw formula (7)

$i_{\mathrm{<figure-callout\; id="1"\; label="N"\; filenames="Y200820111620E00161.png,Y200820111620E00162.png"\; state="\{\{state\}\}">N</figure-callout>}1}=-\frac{N_2}{{\mathrm{<figure-callout\; id="1"\; label="N"\; filenames="Y200820111620E00161.png,Y200820111620E00162.png"\; state="\{\{state\}\}">N</figure-callout>}}_1}\&times;i_{\mathrm{PFC}}...\left(7\right)$

So,, promptly draw formula (8) according to two formulas (4), (7)

$i_m=i_{\mathrm{CB}}-{\mathrm{<figure-callout\; id="1"\; label="i\; N"\; filenames="Y200820111620E00161.png,Y200820111620E00162.png"\; state="\{\{state\}\}">i</figure-callout>}}_N=i_{\mathrm{CB}}+\frac{N_2}{{\mathrm{<figure-callout\; id="1"\; label="N"\; filenames="Y200820111620E00161.png,Y200820111620E00162.png"\; state="\{\{state\}\}">N</figure-callout>}}_1}\&times;i_{\mathrm{PFC}}...\left(8\right)$

Therefrom as can be seen, when diverter switch Q1 conducting, the excitatory energy of transformer Tr comes from energy storage capacitor C1 and input ac voltage Vin.

With reference to figure 3C and Fig. 3 D, in the stage, diverter switch Q1 ends at b, and the rectifier diode D7 conducting of transformer Tr primary side at this moment, is stored in the excitatory energy among the transformer Tr, discharges to output capacitance C2 by rectifier diode D7.Simultaneously, input ac voltage Vin discharges path by the coupling winding N2 of elementary winding N1, the transformer Tr of second rectifier 202, transformer Tr and the energy of energy storage capacitor C1 formation energy-storage reactor LPFC.

At this moment, the energy of energy-storage reactor LPFC and coupling winding N2, its part is directly delivered to the primary side of transformer Tr, and another part energy is then given energy storage capacitor C1 charging, drops to zero up to energy-storage reactor LPFC electric current.Like this, energy among the coupling winding N2 just can obtain loopback, with the energy that reduces coupling winding N2 the peak voltage that causes between extreme and the source terminal of letting out, and then reduce the caused loss of leakage inductance of coupling winding N2 and the switching loss of diverter switch Q1 at diverter switch Q1.

When diverter switch Q1 ended, the current equation formula (9) of energy-storage reactor LPFC was:

$L_{\mathrm{PFC}}\frac{{\mathrm{di}}_{\mathrm{PFC}}}{\mathrm{dt}}=U_{\mathrm{in}}\left|\sin \mathrm{\&omega;t}\right|-U_{\mathrm{CB}}-\frac{{N_1-N}_2}{N_3}\&times;U_o...\left(9\right)$

The current equation formula (10) of magnetizing inductance is:

$L_m\frac{{\mathrm{di}}_m}{\mathrm{dt}}=-\frac{N_1}{N_3}{\&times;U}_o...\left(10\right)$

Again, i _PFC=-i _m-i _N1... (11)

According to the principle of ampere-turn equilibrium, draw formula (12)

N ₂×i _PFC+N ₁×i _N1+N ₃×i _D＝0 ...(12)

Then, before energy-storage reactor LPFC and magnetizing inductance electric current were all interrupted, the current i D that flows through the rectifier diode D7 of transformer Tr primary side can be represented by formula (13):

$i_D=-\frac{N_2}{N_3}\&times;i_{\mathrm{PFC}}-\frac{N_1}{N_3}\&times;i_{\mathrm{<figure-callout\; id="1"\; label="N"\; filenames="Y200820111620E00161.png,Y200820111620E00162.png"\; state="\{\{state\}\}">N</figure-callout>}1}=-\frac{N_2}{N_3}\&times;i_{\mathrm{PFC}}+\frac{N_1}{N_3}\&times;(i_{\mathrm{PFC}}+i_m)...\left(13\right)$

After formula (13) arrangement, promptly obtain formula (14)

$i_D=-\frac{N_2}{N_3}\&times;i_{\mathrm{PFC}}-\frac{N_1}{N_3}\&times;i_{\mathrm{<figure-callout\; id="1"\; label="N"\; filenames="Y200820111620E00161.png,Y200820111620E00162.png"\; state="\{\{state\}\}">N</figure-callout>}1}=\frac{{N_1-N}_2}{N_3}\&times;i_{\mathrm{PFC}}+\frac{N_1}{N_3}\&times;i_m...\left(14\right)$

Equally as can be seen, the energy that is transferred to transformer Tr primary side also has the part that is directly delivered to output from energy-storage reactor LPFC except the excitatory part in the transformer.Generally, the electric current of energy-storage reactor LPFC can be at first interrupted, and from waveform, the current waveform of rectifier diode D7 can present the shape of broken line.

With reference to figure 4, in the stage, the excitatory energy of transformer Tr continues to charge to output capacitance C2 by rectifier diode D7, drops to zero up to exciting curent at c again.And, too high in order to prevent power supply frequency when the underloading at d in the stage, adopt usually and decide FREQUENCY CONTROL or the control of frequency conversion rate, limiting simultaneously the deadline of diverter switch Q1, so, in primary side and all no current existence of primary side of transformer Tr.

With reference to figure 5, be the device circuit schematic diagram of the utility model second embodiment.The identical person with first embodiment of assembly in the utility model second embodiment indicates with same-sign.Second embodiment is identical with the effect of reaching with the circuit operation principle of first embodiment, its main difference be in: the flyback conversion equipment 300 of second embodiment has increased by two groups of clampers, wherein first forward the diode D8 capacitor C 3 that is coupled to a parallel connection constitute first clamper with resistance R 1, second forward diode D9 be coupled to capacitor C in parallel 3 and resistance R 1, to constitute second clamper.First clamper is coupled to diverter switch Q1, and after being used for limiting diverter switch Q1 and ending, transformer Tr leakage inductance is at the caused oscillating voltage in diverter switch Q1 two ends.Wherein, first forward diode D8 the oscillating voltage that diverter switch Q1 two ends are produced is directed to capacitor C in parallel 3 and is discharged with resistance R 1.In addition, the voltage at diode D5, D6 two ends can be clamped at the terminal voltage of energy storage capacitor C1 by diode D1, D2.

Be coupled to second rectifier 202 with reference to figure 5, the second clampers again, after ending in order to inhibition diverter switch Q1, the oscillating voltage that this second rectifier 202 is produced.Second diode D9 the oscillating voltage that second rectifier 202 is produced forward wherein, being directed to capacitor C in parallel 3 is discharged with resistance R 1, after ending with restriction diverter switch Q1, the interelectrode capacitance vibration of energy storage inductor LPFC and diode D3, D4, the oscillating voltage at caused diode D3, D4 two ends.

With reference to figure 6, be the device circuit schematic diagram of the utility model the 3rd embodiment.The identical person with second embodiment of assembly in the utility model the 3rd embodiment indicates with same-sign.The circuit operation principle of the 3rd embodiment and second embodiment is identical with the effect of reaching, its main difference be in: the clamper of the flyback conversion equipment 400 of the 3rd embodiment comprises forward diode D8, D9, D10, resistance R 1, R2 and capacitor C 3.The clamper that diode D8, D10, resistance R 1 and capacitor C 3 are constituted, after being used for being limited in diverter switch Q1 and ending, transformer Tr leakage inductance is at the peak value of the caused oscillating voltage in diverter switch Q1 two ends.

In sum, flyback conversion equipment of the present utility model suppresses the voltage of energy storage capacitor by the coupling winding of a transformer of series connection in the loop of PFC inductive current.Simultaneously, energy in energy-storage reactor and the coupling winding, a part will be transmitted to secondary winding by the elementary winding of transformer, another part will charge to energy storage capacitor, to reduce the caused leakage inductance loss of coupling winding, and after reducing diverter switch and ending, peak voltage that is produced and switching loss, and then promote the efficient of converter integral body.

The above only is a preferred implementation of the present utility model; should be pointed out that for those skilled in the art, under the prerequisite that does not break away from the utility model principle; can also make some improvements and modifications, these improvements and modifications also should be considered as protection range of the present utility model.

Claims (10)

1. the flyback conversion equipment with single-stage power factor correction circuit is characterized in that, includes:

Input ac voltage carries out rectification to produce first rectifier of one first full-wave direct current voltage one to one;

The energy storage capacitor that a pair of this first full-wave direct current voltage carries out filtering is coupled between this first rectifier and the earth terminal;

A pair of this input ac voltage carries out rectification to produce second rectifier of one second full-wave direct current voltage;

The energy-storage reactor that a pair of this second full-wave direct current voltage carries out energy storage is coupled to this second rectifier;

One switches switch, is coupled to this earth terminal; And

One has the transformer of an elementary winding and a coupling winding, and wherein this elementary winding and this diverter switch coupled in parallel be in this energy storage capacitor, and this be coupled winding and this diverter switch coupled in series are in this energy-storage reactor.

2. the flyback conversion equipment with single-stage power factor correction circuit as claimed in claim 1 is characterized in that this transformer also includes the level winding one time, and this secondary winding is coupled to an output capacitance by a rectifier diode.

3. the flyback conversion equipment with single-stage power factor correction circuit as claimed in claim 2 is characterized in that, this rectifier diode is a Schottky diode or a synchronous diode.

4. the flyback conversion equipment with single-stage power factor correction circuit as claimed in claim 2, it is characterized in that, also comprise a controller, this controller is coupled to this output storage capacitor, this controller receives the output voltage on this output storage capacitor, and controls this diverter switch.

5. the flyback conversion equipment with single-stage power factor correction circuit as claimed in claim 2, it is characterized in that, this first rectifier is at this input ac voltage during greater than the voltage on this energy storage capacitor, exports this first full-wave direct current voltage with to this energy storage capacitor charging.

6. the flyback conversion equipment with single-stage power factor correction circuit as claimed in claim 2 is characterized in that, is connected with a public rectifier diode between this first rectifier and this second rectifier.

7. the flyback conversion equipment with single-stage power factor correction circuit as claimed in claim 2 is characterized in that, also comprises one first clamper, and this first clamper is coupled to this diverter switch.

8. the flyback conversion equipment with single-stage power factor correction circuit as claimed in claim 7 is characterized in that, this first clamper comprise one first forward diode be coupled to the capacitance-type resistor group of a parallel connection.

9. the flyback conversion equipment with single-stage power factor correction circuit as claimed in claim 7 is characterized in that, also comprises one second clamper, and this second clamper is coupled to this second rectifier.

10. the flyback conversion equipment with single-stage power factor correction circuit as claimed in claim 9 is characterized in that, this second clamper comprise one second forward diode be coupled to this capacitance-type resistor group in parallel.

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