CN102904433A - Power-factor control circuit and control method thereof - Google Patents

Abstract

The invention relates to a power-factor control circuit and a control method thereof. A power-factor controller is utilized for judging that whether the operation of the power-factor control circuit is in a continuous current mode or a discontinuous current mode, and a corresponding pulse width modulation signal is output to the power-factor control circuit according to a judgment result; the duty period of the pulse width modulation signal is the sum of a feedforward control parameter and a current compensation parameter, and the current compensation parameter comprises an error value of a reference current and an inductive current in the power-factor control circuit; and therefore, a replaceable power supply circuit can obtain the corresponding pulse width modulation signal depending on an internal current mode, and a harmonic defect is effectively improved.

Description

Power factor control circuit and control method thereof

Technical field

The present invention is a kind of power factor control circuit and control method thereof, refers to especially export according to exchangeable type power supply circuit estimated current pattern control circuit and the control method of corresponding pulse-width modulation signal.

Background technology

Please refer to shown in Figure 5ly, wish is converted to DC power supply with the AC power (Vac) of civil power and uses for load 60, ties up between AC power (Vac) and the load 60 to be connected a rectifier 50 and an exchangeable type power supply circuit 70.This rectifier 50 is converted to direct current string wave voltage with AC power; The input of this exchangeable type power supply circuit 70 connects the output of this rectifier 50, direct current string wave voltage be converted to a galvanic current source and export load 60 to by its output, wherein this exchangeable type power supply circuit 70 includes a circuit of power factor correction 71 and a DC-DC converter 72, exports to load 60 after the voltage (such as 380V) of this circuit of power factor correction 71 outputs being converted to the direct voltage (such as 28V, 12V) of different levels by this DC-DC converter 72 again.

This circuit of power factor correction 71 consists predominantly of an inductance L, an output capacitance C and initiatively switch 711, one first proportional integral amplifier 81, one second proportional integral amplifier 82, a multiplexer 83 and a driver 84; Wherein, be connected with this active switch 711 between this inductance L and the output capacitance C, wherein this active switch 711 has a control end.

Above-mentioned the first proportional integral amplifier 81 has two inputs and connects respectively output and a reference voltage V of this circuit of power factor correction 71 _Ref1, and have an output and connect this multiplexer 83, this multiplexer 83 connects the output of these rectifiers 50.

Above-mentioned the second proportional integral amplifier 82 has two inputs and connects respectively the output of these rectifier 50 outputs and this multiplexer 83.

This driver 84 has two inputs and is electrically connected respectively output and a reference voltage signal V of this second proportional integral amplifier 82 _Ref2, and the output of driver 84 connects the control end of this active switch 711.

The control method of known power factor cooperates the foregoing circuit structure to be illustrated as rear.This first proportional integral amplifier 81 is according to these circuit of power factor correction 71 actual output voltages and this reference voltage V _Ref1Difference and export a voltage error signal V _ErrorThis second proportional integral amplifier 82 is according to inductive current I _LWith voltage error signal V _ErrorOutput one represents the voltage signal I of current error _ErrorTo this driver 84, this driver 84 is according to this voltage signal I again _ErrorWith reference voltage signal V _Ref2Export a pulse-width modulation signal to the control end of active switch 711, with the responsibility cycle (Duty cycle, D) of controlling these active switch 711 conductings.

Hold above-mentionedly, want to make the stable voltage V of this circuit of power factor correction 71 outputs one _Out, then responsibility cycle, actual input voltage V _{In, sense}With default output voltage V _OutThere is a relational expression: Because of the responsibility cycle of pulse-width modulation signal system according to voltage signal I _ErrorAnd get voltage signal I again _ErrorThe actual input voltage, the inductive current I that include this circuit of power factor correction 71 _LWith the composition of actual output voltage, therefore see through the suitable configuration of circuit of power factor correction, power factor is improved.

Comprehensively the above needs only these circuit of power factor correction 71 actual output voltages and this reference voltage V _Ref1Between variant, and the inductive current IL electric current of this circuit of power factor correction 71 and voltage error signal V _ErrorBetween when variant, this driver 84 can corresponding output pulse width modulating signal.

Exchangeable type power supply circuit can operate in different current-modes because load condition changes, and includes continuous current mode (Continuous Current Mode, CCM) and discontinuous current pattern (Discrete Current Mode, DCM).

When exchangeable type power supply circuit operated in continuous current mode, during the responsibility cycle (Duty cycle) of pulse-width modulation signal, this active switch 711 was switched on, and made this inductance L charging, and promoted the electric current by inductance L; During the responsibility cycle of non-pulse-width modulation signal, initiatively switch 711 cut-offs, make this inductance L discharge, and be discharged to before zero in this inductance L, even this pulse-width modulation signal initiatively switch 711 is switched on once again, inductance L is recharged to higher electric current level, and repeatedly in the process of charge and discharge, the average current waveform of inductance L will be followed the voltage waveform of input in inductance L.

When this circuit of power factor correction 71 operated in the discontinuous current pattern, the relative continuous current mode of electric current was low; During the responsibility cycle of pulse-width modulation signal, this active switch 711 is switched on, and makes this inductance L charge to promote electric current by inductance L; During the responsibility cycle of non-pulse-width modulation signal, inductance L will discharge into zero, and in be recharged during the responsibility cycle next time; Therefore the relative continuous current mode of average current by inductance L is low.

Disclose in the circuit structure that improves power factor such as Fig. 5, if the responsibility cycle of pulse-width modulation signal has been designed to meet continuous current mode, although really can improve the power factor when operating in continuous current mode, but also so that when this circuit of power factor correction 71 operates in the discontinuous current pattern, the responsibility cycle when the pulse-width modulation signal is still continued to use continuous current mode; The pulse-width modulation signal is during non-responsibility cycle, and when inductance L discharges into zero, the stored capacitive energy of energy-storage travelling wave tube (such as diode, boost capacitor C etc.) on this circuit of power factor correction 71 will feed back to the input of this circuit of power factor correction 71, cause the serious harmonic distortion of input.

In order to improve above-mentioned shortcoming, please refer to shown in Figure 6, it is the improvement of a circuit of power factor correction 71 ', it is characterized in that, active switch 711 ' in this circuit of power factor correction 71 ' the in parallel one slow unit 73 that shakes, this slow unit 73 that shakes includes a diode 730, a resistance 731 and an electric capacity 732, jointly is connected in series to this electric capacity 732 after this diode 730 and resistance 731 parallel connections again, wherein the anode tap of this diode 730 connects inductance L, and its cathode terminal connects electric capacity 732.By this, when if this circuit of power factor correction 71 ' operates in the discontinuous current pattern, in the pulse-width modulation signal during non-responsibility cycle, the stored portion of energy of energy-storage travelling wave tube on the boost type power circuit (such as inductance L, diode D, boost capacitor C) will be absorbed by the slow unit 73 that shakes, and be that effective reduction boost type power circuit is in the situation of its input harmonic distortion.

Only, diode 730, the resistance 731 that should delay in the unit 73 that shake are passive devices with electric capacity 732, to in the process of these circuit of power factor correction 71 conversions, consume energy, cause reducing the conversion efficiency of boost type power circuit, and can make input current produce low-frequency oscillation.

Please refer to shown in Figure 7ly, existing researcher proposes a control circuit, mainly judges first at present operated current-mode of exchangeable type power supply circuit, again according to the corresponding responsibility cycle that changes the pulse-width modulation signal of estimated current pattern.

This control circuit includes a rectifier 90 and a circuit of power factor correction 91 equally; Wherein the input of this rectifier 90 connects electric main (Vac), the input of this circuit of power factor correction 91 is electrically connected the output of this rectifier 90, and this circuit of power factor correction 91 includes an inductance L, a capacitor C, initiatively switch 910 and a power factor controller 92.

Above-mentioned rectifier 90 is to receive electric main (Vac), and is converted to behind the direct current string ripple power supply this electric main and output.

The input V of above-mentioned circuit of power factor correction 91 _InBe electrically connected the output of this rectifier 90, it is operable in continuous current mode or discontinuous current pattern; This circuit of power factor correction 91 illustrates it with boost circuit.

The input of this power factor controller 92 is electrically connected input and the output of this circuit of power factor correction 91, to capture the input voltage V of this circuit of power factor correction 91 _{In, sense}, output voltage V _{Out, sense}With this inductive current I _{L, sense}, and this power factor controller 92 has an output control terminal and is electrically connected this active switch 910.

Please refer to shown in Figure 8ly, have an arithmetic element 923 in this power factor controller 92, and power factor controller 92 includes a continuous current mode 921 and a discontinuous current pattern 922.

According to the characteristic relation of power factor correction, this fortune arithmetic element 923 is according to two arithmetic expressions $D_1=\sqrt{\frac{2L}{V_{\mathrm{in},\mathrm{sense}}{T}_S}\·i_{\mathrm{REF}}\·(1-\frac{V_{\mathrm{in},\mathrm{sense}}}{V_{\mathrm{out},\mathrm{sense}}})}$ And $D_2=1-\frac{V_{\mathrm{in},\mathrm{sense}}}{V_{\mathrm{out},\mathrm{sense}}}$ Between size, if D2＜D1 then is judged as continuous current mode, 92 of this power factor controllers switch to continuous current mode 921, and can export a responsibility cycle from its output control terminal are $D=(1-\frac{V_{\mathrm{in},\mathrm{sense}}}{V_{\mathrm{out}}})+\left[\frac{L}{V_{\mathrm{out}}{T}_S}(i_{\mathrm{REF}}-I_{L,\mathrm{sense}})\right]$ The pulse-width modulation signal, wherein

Be a theoretical value,

It is a compensating parameter; If D1＜D2 then is judged as the discontinuous current pattern, 92 of this power factor controllers switch to discontinuous current pattern 921, and can export a responsibility cycle from its output control terminal are The pulse-width modulation signal, and Be a theoretical value:

L: inductance value;

V _{In, sense}: input voltage;

V _{Out, sense}: output voltage;

V _Out: rated output voltage;

T _s: the cycle of pulse-width modulation signal.

i _REF: output voltage V _{Out, sense}And the parameter of the error amount between the reference voltage after proportional integral amplifies.

Be can initiatively change the pulse-width modulation signal of output according to the operator scheme of current power factor correcting circuit 91 with, this power factor controller 92, improving by this pulse-width modulation signal and circuit of power factor correction 91 can't be corresponding and cause the situation of harmonic wave.

When circuit of power factor correction 91 operated in continuous current mode, responsibility cycle system included a theoretical value and a compensating parameter, is supplied the deficiency of theoretical value by compensating parameter; Even so, when circuit of power factor correction 91 operates in the discontinuous current pattern, the responsibility cycle of power factor controller 92 outputs

It only is a theoretical value, assume you as a matter of course, when power factor controller 92 switches to discontinuous current pattern 922, only theoretical value is directly overlapped the circuit that is used in reality, therefore improve the effect of harmonic distortion limited (input voltage as shown in Figure 9, current waveform figure), the space of improvement still arranged.

Summary of the invention

Therefore main purpose of the present invention provides a kind of power factor control circuit, to improve the harmonic distortion defective of known control circuit.

Take off purpose for before reaching, the technological means system that the present invention adopts makes this power factor control circuit comprise an inductance, an output capacitance, a diode, initiatively switch and a power factor controller; Wherein, this power factor controller is electrically connected input and the output of this power factor control circuit, and has an output control terminal and be electrically connected this active switch;

This power factor controller operates in continuous current mode or discontinuous current pattern and corresponding output distinct pulse widths modulating signal according to this power factor control circuit; Wherein:

The responsibility cycle of the pulse-width modulation signal of corresponding continuous current mode output is the sum total of a feedfoward control parameter and a current compensation parameter;

The responsibility cycle of the pulse-width modulation signal of corresponding discontinuous current pattern output is the sum total of a feedfoward control parameter and a current compensation parameter; Wherein this current compensation system of parameters includes the error amount of a reference current and this inductive current.

The present invention still provides a kind of power factor control method, and its step comprises:

Judge that the estimated current operator scheme is continuous current mode or discontinuous current pattern;

If be judged as continuous current mode, then corresponding continuous current mode is exported a pulse-width modulation signal, its responsibility cycle is the sum total of a feedfoward control parameter and a current compensation parameter, and wherein this current compensation system of parameters includes the error amount of a reference current and this inductive current;

If be judged as the discontinuous current pattern, then corresponding discontinuous current pattern is failed a pulse-width modulation signal, its responsibility cycle is the sum total of a feedfoward control parameter and a current compensation parameter, and wherein this current compensation system of parameters includes the error amount of a reference current and this inductive current.

Control method of the present invention can be along with the operated different current-modes of exchangeable type power supply circuit, the pulse-width modulation signal of output correspondence is to exchangeable type power supply circuit, to satisfy simultaneously when load that exchangeable type power supply circuit the was connected demand as heavy duty or underloading, therefore effectively improve harmonic wave.

Description of drawings

Fig. 1: boost type power circuit and power factor controller connection diagram.

Fig. 2: power factor controller detailed maps.

Fig. 3: through input voltage, the current waveform figure of current compensation.

Fig. 4: buck power circuit and power factor controller connection diagram.

Fig. 5: known exchangeable type power supply circuit and power factor control circuit connection diagram.

Fig. 6: the exchangeable type power supply circuit that another is known and power factor controller connection diagram.

Fig. 7: known exchangeable type power supply circuit and a power factor controller connection diagram again.

Fig. 8: the power factor controller schematic diagram among Fig. 7.

Fig. 9: the exchangeable type power supply circuit input voltage among Fig. 7, current waveform schematic diagram.

The main element symbol description:

Embodiment

Fig. 1 is the circuit diagram of power factor control circuit of the present invention, wherein this power factor control circuit 20 is to see through a rectifier 10 to connect an AC power (Vac), by this rectifier 10 this AC power is converted to a direct current string ripple power supply, obtains direct current string ripple power supply in input.This power factor control circuit 20 can be a boost type power supply structure (Boost converter) or buck power supply structure (Buck converter), all is operable in continuous current mode or discontinuous current pattern; The present embodiment system illustrates with the boost type power supply structure, and this power factor control circuit 20 is to include an inductance L, a diode D, an output capacitance C, a resistance R, initiatively switch 21 and a power factor controller 30.

This inductance L, diode D, output capacitance C are connected in series with resistance R and consist of a loop with this rectifier 10; This active switch 21 is electrically connected between the anode tap and this resistance R of this diode D, and this active switch 21 has a control end; The two ends of this output capacitance C are as the output V of voltage _Out Power factor controller 30 connects between the input and output of this power factor control circuit 20, and has the control end that an output control terminal connects active switch 21.

Please refer to shown in Figure 2ly, this power factor controller 30 includes a voltage circuit control module 31, a current circuit control module 32 and a feedfoward control module 33.

This voltage circuit control module 31 comprises a CCM proportional integral amplifying unit 310 and a DCM proportional integral amplifying unit 311; This CCM proportional integral amplifying unit 310 has the scale parameter K under continuous current mode _{P, CCM}, integral parameter K _{I, CCM}, this DCM proportional integral amplifying unit 311 has the scale parameter K under the discontinuous current pattern _{P, DCM}, integral parameter K _{I, DCM}These voltage circuit control module 31 inputs are electrically connected a reference voltage V _RefAnd the input of this power factor control circuit 20 and output, in order to obtain reference voltage V _RefWith power factor control circuit 20 output voltage V _{Out, sense}Difference, and difference seen through CCM proportional integral amplifying unit 310 or DCM proportional integral amplifying unit 311 carry out after proportional integral amplifies, with the input voltage V of power factor control circuit 20 reality _{In, sense}Multiply each other, represent reference current i to form one _REFSignal output.

This current circuit control module 32 is electrically connected the output of this voltage circuit control module 31 and the resistance R of this power factor control circuit 20, and has described output control terminal, by the inductive current I of resistance R reaction power factor control circuit 20 _{L, sense}, this current circuit control module 32 receives reference current i _REFWith inductive current I _{L, sense}And subtract each other, to obtain its difference i _REF-I _{L, sense}This current circuit control module 32 comprises a continuous current compensating unit 321 and a discontinuous current compensating unit 322, and each compensating unit 321,322 produces respectively a current compensation parameter according to aforementioned difference; According to the characteristic relation of power factor correction, with the boost type power circuit, the current compensation parameter that continuous current compensating unit 321 produces is

The current compensation parameter that this discontinuous current compensating unit 322 produces is F _m(i _REF-I _{L, sense}), wherein:

L: inductance value;

V _Out: rated output voltage;

I _{L, sense}: inductive current;

F _m: penalty constant;

i _REF: comprise output voltage V _{Out, sense}The reference current of composition.

The input of this feedfoward control module 33 is electrically connected the output of this voltage circuit control module 31 and output and the input of this power factor control circuit 20, one output control terminal of this feedfoward control module 33 is electrically connected this current circuit control module 32, and another output control terminal then connects this voltage circuit control module 33; This feedfoward control module 33 is the input voltage V according to power factor control circuit 20 _{In, sense}, output voltage V _{Out, sense}Reference current i with these voltage circuit control module 31 outputs _REFJudge that this power factor control circuit 20 operates in continuous current mode or discontinuous current pattern, and according to the corresponding CCM proportional integral amplifying circuit 310 and DCM proportional integral amplifying circuit that switches in this voltage circuit control module 31 of each current-mode, and the continuous current compensating unit in the corresponding switch current circuit controls module 32 321 and discontinuous current compensating unit 322; This feedfoward control module 33 and the feedfoward control parameter that produces a corresponding current pattern are to this current circuit control module 32; This current circuit control module 32 outputs one pulse-width modulation signal is to beginning 21 initiatively, and wherein the responsibility cycle of this pulse-width modulation signal is the summation of the current compensation parameter that this feedfoward control parameter and this current circuit control module 31 produce.

As described in prior art, general judgment mode, this feedfoward control module 33 is according to two arithmetic expressions $D_1=\sqrt{\frac{2L}{V_{\mathrm{in},\mathrm{sense}}{T}_S}\·i_{\mathrm{REF}}\·(1-\frac{V_{\mathrm{in},\mathrm{sense}}}{V_{\mathrm{out},\mathrm{sense}}})}$ And $D_2=1-\frac{V_{\mathrm{in},\mathrm{sense}}}{V_{\mathrm{out},\mathrm{sense}}}$ Between size, if D1＜D2 judges that then this boost type power circuit operates in the discontinuous current pattern, according to the characteristic relation of power factor correction, the feedfoward control parameter that produces is

If D2＜D1 then is judged as continuous current mode, and the feedfoward control parameter that produces is

Wherein:

L: inductance value;

V _{In, sense}: input voltage;

V _{Out, sense}: output voltage;

V _Out: rated output voltage;

T _s: the cycle of pulse-width modulation signal.

For example, when this feedfoward control module 33 judges that power factor control circuit 20 operates in continuous current mode, be that voltage circuit control module 31 is switched to CCM proportional integral amplifying unit 310, make voltage circuit control module 31 export ratio parameter K _{P, CCM}With integral parameter K _{I, CCM}, and this current circuit control module 32 switched to continuous current compensating unit 321, make continuous current compensating unit 321 generation current compensating parameters be This feedfoward control module 33 also produces the feedfoward control parameter

And the feedfoward control parameter is outputed to this current circuit control module 32, this current circuit control module 32 with feedfoward control parameter and the addition of current compensation parameter after, export a responsibility cycle and be $D=(1-\frac{V_{\mathrm{in},\mathrm{sense}}}{V_{\mathrm{out}}})+\left[\frac{L}{V_{\mathrm{out}}{T}_S}(i_{\mathrm{REF}}-I_{L,\mathrm{sense}})\right]$ The pulse-width modulation signal to this control end of switch 21 initiatively, responsibility cycle is the summation of feedfoward control parameter and current compensation parameter.

In like manner, when this feedfoward control module 33 judges that power factor control circuit 20 operates in the discontinuous current pattern, feedfoward control module 33 is switched these voltage circuit control module 31 to DCM proportional integral amplifying units 311, and switch current circuit controls module 32 is to discontinuous current compensating unit 322, and then current circuit control module 32 outputs one responsibility cycle is $D=\sqrt{\frac{2L}{V_{\mathrm{in},\mathrm{sense}}{T}_S}\·i_{\mathrm{REF}}\·(1-\frac{V_{\mathrm{in},\mathrm{sense}}}{V_{\mathrm{out}}})}+F_m(i_{\mathrm{REF}}-I_{L,\mathrm{sense}})$ The pulse-width modulation signal to this control end of switch 21 initiatively.

Comprehensive the above, this feedforward controller 33 can be judged this power factor control circuit 20 and operate in which kind of current-mode, and the proportional integral amplifying unit in the corresponding switched voltage circuit controls module 31 and the current compensation unit in the current circuit control module 32, make current circuit control module 32 export corresponding pulse-width modulation signal to active switch 21 according to each current-mode, again with in the pulse-width modulation signal under each current-mode, mainly be the inductive current I that sees through detection power factor control circuit 20 wherein _{L, sense}, and the reference current i of these voltage circuit control module 31 outputs _REFBetween difference (i _REF-I _{L, sense}) concern with the generation current compensating parameter; Please arrange in pairs or groups with reference to figure 3, Fig. 9 (oscillogram of prior art) with as shown in table 1 below, Fig. 3 is alternating voltage, the current waveform figure of circuit of the present invention in the discontinuous current pattern, by can see among the figure and, the input current I of circuit of the present invention _AcNear input voltage V _AcWaveform, compared to prior art, the present invention is in the discontinuous current pattern, the responsibility cycle of pulse-width modulation signal is $D=\sqrt{\frac{2L}{V_{\mathrm{in},\mathrm{sense}}{T}_S}\·i_{\mathrm{REF}}\·(1-\frac{V_{\mathrm{in},\mathrm{sense}}}{V_{\mathrm{out}}})}+F_m(i_{\mathrm{REF}}-I_{L,\mathrm{sense}}),$ Because of the inductive current I according to reality _{L, sense}With reference current i _REFBetween difference and get, responsibility cycle is non-only to be theoretical value, therefore can more effectively improve the problem of power factor and harmonic wave.

Load capacity	10％	20％	50％	100％
					Known techniques THD	26.87％	17.50％	7.93％	3.28％
Circuit THD of the present invention	17.99％	11.46％	6.84％	3.07％

Table 1: known technology and the present invention improve the comparison sheet of harmonic distortion.

Please refer to shown in Figure 4, in another preferred embodiment, power factor control circuit 20 ' is buck power supply structure (Buck converter), includes an active switch 21 ', a diode D, an inductance L, an output capacitance C and a power factor controller 30 '; Initiatively switch 21 ', this inductance L, this output capacitance C are connected in series and consist of a loop with rectifier 10 ' for these, and this active switch 21 ' has a control end, the anode tap of this diode D connects the output of rectifier 10 ', its cathode terminal is connected between active switch 30 ' and the inductance L, this power factor controller 30 ' connects output and the input of this power factor control circuit 20 ', and has the control end that an output control terminal connects this active switch 21 '.

The arithmetic expression continuous, the discontinuous current pattern that the control method of this preferred embodiment is used for judging is $D_1=\sqrt{\frac{2L}{V_{\mathrm{in},\mathrm{sense}}{T}_S}\·i_{\mathrm{REF}}\·(\frac{V_{\mathrm{out},\mathrm{sense}}}{V_{\mathrm{in},\mathrm{sense}}}-1)},$ $D_2=\frac{V_{\mathrm{out},\mathrm{sense}}}{V_{\mathrm{in},\mathrm{sense}}},$ If D1＜D2 judges that then power factor control circuit 20 ' operates in the discontinuous current pattern, if D2＜D1 judges that then power factor control circuit 20 ' operates in continuous current mode; When if power factor control circuit 20 ' operates in the discontinuous current pattern again, the feedfoward control parameter that feedforward controller produces in the power factor controller 30 ' is This current compensation parameter is F _m(i _REF-I _{L, sense}), so the responsibility cycle of pulse-width modulation signal is When if power factor control circuit 20 ' operates in continuous current mode, the feedfoward control parameter that feedforward controller produces in the power factor controller 30 ' is

And this current compensation parameter is

Therefore the responsibility cycle of pulse-width modulation signal is

Wherein:

L: inductance value;

V _{In, sense}: input voltage;

V _{Out, sense}: output voltage;

V _Out: rated output voltage;

Ts: the cycle of pulse-width modulation signal;

i _REF: comprise output voltage V _{Out, sense}The reference current of composition.

Claims (12)

1. power factor control circuit, it comprises an inductance, an output capacitance, a diode, initiatively switch and a power factor controller; It is characterized in that, described power factor controller is electrically connected input and the output of described power factor control circuit, and has an output control terminal and be electrically connected described active switch;

Described power factor controller operates in continuous current mode or discontinuous current pattern and corresponding output distinct pulse widths modulating signal according to described power factor control circuit; Wherein:

The responsibility cycle of the pulse-width modulation signal of corresponding continuous current mode output is the sum total of a feedfoward control parameter and a current compensation parameter;

The responsibility cycle of the pulse-width modulation signal of corresponding discontinuous current pattern output is the sum total of a feedfoward control parameter and a current compensation parameter; Wherein said current compensation system of parameters includes the error amount of a reference current and described inductive current.

2. power factor control circuit as claimed in claim 1 is characterized in that, in the responsibility cycle of the pulse-width modulation signal that the discontinuous current pattern is exported, its current compensation parameter is that error amount is multiplied by a penalty constant.

3. power factor control circuit as claimed in claim 1 or 2 is characterized in that, described power factor controller includes:

One voltage circuit control module is to produce described reference current according to the output voltage of described power factor control circuit and the difference of a reference voltage, and it comprises a CCM proportional integral amplifying unit and a DCM proportional integral amplifying unit;

One current circuit control module, be electrically connected output and the described power factor control circuit of described voltage circuit control module, be used for output one pulse-width modulation signal to described active switch, it comprises a continuous current compensating unit and a discontinuous current compensating unit, according to the inductive current of power factor control circuit and produce respectively described current compensation parameter;

One feedfoward control module, its input is electrically connected the output of described voltage circuit control module and output and the input of described power factor control circuit, one output control terminal of described feedfoward control module is electrically connected described current circuit control module, and another output control terminal is electrically connected described voltage circuit control module;

Described feedfoward control module judges that described power factor control circuit operates in continuous current mode or discontinuous current pattern, and according to the corresponding extremely described current circuit control module of described feedfoward control parameter that produces of each current-mode, and the CCM proportional integral amplifying unit in the corresponding switched voltage circuit controls module and DCM proportional integral amplifying unit, and continuous current compensating unit and discontinuous current compensating unit in the switch current circuit controls module, the responsibility cycle that makes described current circuit control module output pulse width modulating signal is the summation of front described feedforward control signal and described current compensation parameter.

4. power factor control circuit as claimed in claim 3, it is characterized in that, described inductance, described diode, described output capacitance are connected in series and consist of a loop with a rectifier, described active switch is electrically connected between the output of the anode tap of described diode and described rectifier, and described current circuit control module has described output control terminal; Wherein:

The responsibility cycle of described pulse-width modulation signal in continuous current mode is $D=(1-\frac{V_{\mathrm{in},\mathrm{sense}}}{V_{\mathrm{out}}})+\left[\frac{L}{V_{\mathrm{out}}{T}_S}(i_{\mathrm{REF}}-I_{L,\mathrm{sense}})\right],$ Wherein said feedfoward control parameter is

The current compensation parameter is

The responsibility cycle of described pulse-width modulation signal in the discontinuous current pattern is $D=\sqrt{\frac{2L}{V_{\mathrm{in},\mathrm{sense}}{T}_S}\·i_{\mathrm{REF}}\·(1-\frac{V_{\mathrm{in},\mathrm{sense}}}{V_{\mathrm{out}}})}+F_m(i_{\mathrm{REF}}-I_{L,\mathrm{sense}}),$ Wherein said feedfoward control parameter is

The current compensation parameter is F _m(i _REF-I _{L, sense}), wherein:

L: inductance value;

V _{In, sense}: input voltage;

V _{Out, sense}: output voltage;

V _Out: rated output voltage;

I _{L, sense}: inductive current;

T _s: the cycle of described pulse-width modulation signal;

F _m: penalty constant;

i _REF: comprise output voltage V _{Out, sense}The reference current of composition.

5. power factor control circuit as claimed in claim 4 is characterized in that, described feedfoward control module is according to two arithmetic expressions $D_1=\sqrt{\frac{2L}{V_{\mathrm{in},\mathrm{sense}}{T}_S}\·i_{\mathrm{REF}}\·(1-\frac{V_{\mathrm{in},\mathrm{sense}}}{V_{\mathrm{out},\mathrm{sense}}})}$ And $D_2=1-\frac{V_{\mathrm{in},\mathrm{sense}}}{V_{\mathrm{out},\mathrm{sense}}}$ Between size, if D1＜D2 judges that then described power factor control circuit operates in the discontinuous current pattern; If D2＜D1 then is judged as continuous current mode, wherein:

L: inductance value;

_{Vin, sense}: input voltage;

V _{Out, sense}: output voltage;

T _s: the cycle of described pulse-width modulation signal;

i _REF: comprise output voltage V _{Out, sense}The reference current of composition.

6. power factor control circuit as claimed in claim 3, it is characterized in that, described active switch, described inductance, described output capacitance are connected in series and consist of a loop with a rectifier, and described active switch has a control end, the anode tap of described diode connects the output of rectifier, its cathode terminal is connected between active switch and the inductance, and described current circuit control module has described output control terminal; Wherein:

The responsibility cycle of described pulse-width modulation signal in continuous current mode is

Wherein said feedfoward control parameter is

The current compensation parameter is

The responsibility cycle of described pulse-width modulation signal in the discontinuous current pattern is

Wherein said feedfoward control parameter is

The current compensation parameter is F _m(i _REF-I _{L, sense}), wherein:

L: inductance value;

V _{In, sense}: input voltage;

V _{Out, sense}: output voltage;

V _Out: rated output voltage;

Ts: the cycle of pulse-width modulation signal;

i _REF: comprise output voltage V _{Out, sense}The reference current of composition.

7. power factor control circuit as claimed in claim 6 is characterized in that, described feedfoward control module is according to two arithmetic expressions $D_1=\sqrt{\frac{2L}{V_{\mathrm{in},\mathrm{sense}}{T}_S}\·i_{\mathrm{REF}}\·(\frac{V_{\mathrm{outsense}}}{V_{\mathrm{in},\mathrm{sense}}}-1)},$ $D_2=\frac{V_{\mathrm{out},\mathrm{sense}}}{V_{\mathrm{in},\mathrm{sense}}},$ If D1＜D2 judges that then described power factor control circuit operates in the discontinuous current pattern, if D2＜D1 then is judged as continuous current mode; Wherein:

L: inductance value;

V _{In, sense}: input voltage;

V _{Out, sense}: output voltage;

Ts: the cycle of pulse-width modulation signal;

i _REF: comprise output voltage V _{Out, sense}The reference current of composition.

8. a power factor control method is characterized in that, described power factor control method comprises following steps:

Judge that the estimated current operator scheme is continuous current mode or discontinuous current pattern;

If be judged as continuous current mode, then corresponding continuous current mode is exported a pulse-width modulation signal, its responsibility cycle is the sum total of a feedfoward control parameter and a current compensation parameter, and wherein said current compensation system of parameters includes the error amount of a reference current and described inductive current;

If be judged as the discontinuous current pattern, then corresponding discontinuous current pattern is failed a pulse-width modulation signal, its responsibility cycle is the sum total of a feedfoward control parameter and a current compensation parameter, and wherein said current compensation system of parameters includes the error amount of a reference current and described inductive current.

9. power factor control method as claimed in claim 8 is characterized in that, the responsibility cycle of above-mentioned pulse-width modulation signal for continuous current mode is $D=(1-\frac{V_{\mathrm{in},\mathrm{sense}}}{V_{\mathrm{out}}})+\left[\frac{L}{V_{\mathrm{out}}{T}_S}(i_{\mathrm{REF}}-I_{L,\mathrm{sense}})\right],$ Wherein said feedfoward control parameter is The current compensation parameter is

The responsibility cycle of above-mentioned pulse-width modulation signal for the discontinuous current pattern is $D=\sqrt{\frac{2L}{V_{\mathrm{in},\mathrm{sense}}{T}_S}\·i_{\mathrm{REF}}\·(1-\frac{V_{\mathrm{in},\mathrm{sense}}}{V_{\mathrm{out}}})}+F_m(i_{\mathrm{REF}}-I_{L,\mathrm{sense}}),$ Wherein said feedfoward control parameter is The current compensation parameter is F _m(i _REF-I _{L, sense}), wherein:

L: inductance value;

V _{In, sense}: input voltage;

V _{Out, sense}: output voltage;

V _Out: rated output voltage;

I _{L, sense}: inductive current;

T _s: the cycle of described pulse-width modulation signal;

F _m: penalty constant;

i _REF: comprise output voltage V _{Out, sense}The reference current of composition.

10. power factor control method as claimed in claim 9 is characterized in that, in judging that the estimated current operator scheme is in the step of continuous current mode or discontinuous current pattern, is according to two arithmetic expressions $D_1=\sqrt{\frac{2L}{V_{\mathrm{in},\mathrm{sense}}{T}_S}\·i_{\mathrm{REF}}\·(1-\frac{V_{\mathrm{in},\mathrm{sense}}}{V_{\mathrm{out},\mathrm{sense}}})}$ And $D_2=1-\frac{V_{\mathrm{in},\mathrm{sense}}}{V_{\mathrm{out},\mathrm{sense}}}$ Between size, if D1＜D2 judges that then described power factor control circuit operates in the discontinuous current pattern; If D2＜D1 then is judged as continuous current mode, wherein:

L: inductance value;

V _{In, sense}: input voltage;

V _{Out, sense}: output voltage;

T _s: the cycle of described pulse-width modulation signal;

i _REF: comprise output voltage V _{Out, sense}The reference current of composition.

11. power factor control method as claimed in claim 8 is characterized in that, the responsibility cycle of above-mentioned pulse-width modulation signal for continuous current mode is Wherein said feedfoward control parameter is

The current compensation parameter is

The responsibility cycle of above-mentioned pulse-width modulation signal for the discontinuous current pattern is Wherein said feedfoward control parameter is

The current compensation parameter is F _m(i _REF-I _{L, sense}), wherein:

L: inductance value;

V _{In, sense}: input voltage;

V _{Out, sense}: output voltage;

V _Out: rated output voltage;

Ts: the cycle of pulse-width modulation signal;

i _REF: comprise output voltage V _{Out, sense}The reference current of composition.

12. power factor control method as claimed in claim 11 is characterized in that, in judging that the estimated current operator scheme is in the step of continuous current mode or discontinuous current pattern, is according to two arithmetic expressions $D_1=\sqrt{\frac{2L}{V_{\mathrm{in},\mathrm{sense}}{T}_S}\·i_{\mathrm{REF}}\·(\frac{V_{\mathrm{out},\mathrm{sense}}}{V_{\mathrm{in},\mathrm{sense}}}-1)},$ $D_2=\frac{V_{\mathrm{out},\mathrm{sense}}}{V_{\mathrm{in},\mathrm{sense}}},$ If D1＜D2 judges that then described power factor control circuit operates in the discontinuous current pattern, if D2＜D1 then judges at continuous current mode; Wherein:

L: inductance value;

V _{In, sense}: input voltage;

V _{Out, sense}: output voltage;

Ts: the cycle of pulse-width modulation signal;

i _REF: comprise output voltage V _{Out, sense}The reference current of composition.

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