CN1380736A

CN1380736A - Non-ringing zero-potential switching method for power converter and its converter

Info

Publication number: CN1380736A
Application number: CN01110476A
Authority: CN
Inventors: 梁锦宏
Original assignee: TIANWANG ELECTRONICS CO Ltd
Current assignee: TIANWANG ELECTRONICS CO Ltd
Priority date: 2001-04-12
Filing date: 2001-04-12
Publication date: 2002-11-20
Anticipated expiration: 2021-04-12
Also published as: CN100481692C; HK1050275A1

Abstract

The invention relates to the switch method without ringing and at zero potential utilzied in power converter as well as the converter. In prior art, when the zero potential switch circuit of the power converter carrier out high-frequency switching process at zero potential in high efficiency, the ringing occurs on the primary side of the transformer caused by the L-C resonant circuit. In the invention, the circuit is adjusted. Thus, when the ringing begins, the current on the inductance is in short circuit, the voltage on the capacitance is clamped so as to eliminate the parasitical ringing. When the operation under high frequency switching, the invention decreases power loss, increases power density greatly and reduces electromagnetic interference.

Description

Be applied to the no ring zero-potential switching method and the transducer of power converter

The present invention relates to a kind of no ring zero-potential switching method and transducer that is applied to power converter, especially refer to that a kind of power converter that makes is in carrying out high efficiency and high density handoff procedure, effectively reduce magnetic loss and the switch switch cost that is produced, and make the withstand voltage no ring zero-potential switching method and the transducer that reduces in the lump of its secondary commutator.

In recent years, in order to catch up with the trend of electronic product fast compactization, the technology of switching power converter develops towards high-frequency, high efficiency and highdensity direction always.Generally speaking, because fet power pipe (Power MOSFE, hereinafter to be referred as power switch pipe) switch speed fast more a lot of than bipolarity pipe (BipolarTransistor), therefore often be widely used in the switching power converter by industry, as the power switch pipe pipe on it, yet, this kind fet power pipe (Power MOSFET) is gone up the energy that parasitic capacitance is retained, when this pipe is switched at every turn, and all can be in its passage, form with ohm heat exhausts, switching frequency is high more, and its loss is big more, this problem, if effectively do not solve, will make this switching power converter be difficult to continue development towards high efficiency and highdensity design object.

Since 1988, the prosperous sesame (C.P.Henze) of the U.S., Martin (H.C.Martin) and Ba Silai three experts such as (D.W.Paraley), jointly on the IEEE publication, delivering zero potential has switched since (ZeroVoltage Switching) notion, various practical circuits promptly are suggested successively, solved the conducting loss problem that is taken place on the fet power pipe (Power MOSFET) traditionally effectively, existing wherein more representative prior art, division is as follows:

1, forward type zero potential commutation circuit (Forward Zero-Voltage Switching PowerConverter):

As shown in Figure 1, be the U.S. 383rd of Bruce Wilkinson in June, 1989 application, the circuit embodiments of No. 594 patents of invention, this patent is by suitably controlling this circuit, make its transformer be operated in positive and negative magnetic region, therefore under identical power output, has the advantage that to select smaller transformer for use.Because the enlightenment of this circuit design, Putrice R.Lethellier has invented the practical circuit that first tool zero potential is switched, as shown in Figure 2, be the U.S. the 4th that gets permission October nineteen ninety, 975, the circuit framework figure of No. 821 patents of invention, this patent reaches the purpose that zero potential is switched, its transformer adopting pine commissure pattern, and on its magnetic stamen, add air gap (gap), to obtain necessary magnetizing inductance and leakage inductance, this magnetizing inductance and leakage inductance can form the L-C resonant circuit with the parasitic capacitance Cs that is connected in parallel on the switch SW 1, make the moment of switch SW 2 after just turning off, resonance because of this L-C resonant circuit, make switch SW 1 obtain the condition that zero potential is switched, similarly, moment after switch SW 1 has just been turned off, also will be because of the resonance of this L-C resonant circuit, make switch SW 2 also obtain the condition that zero potential is switched, at this moment, owing to added air gap and leakage inductance on the magnetic stamen of this transformer, cause the magnetic loss that can not be ignored, make this circuit when obtaining the zero potential switching condition, also the shortcoming of having brought abnormal heating and efficient to glide for this transformer.

As Fig. 3, shown in 4, for Paul Imbertson filed an application in October, 1991, and the U.S. the 5th that gets permission in September, 1993,245, the circuit embodiments of No. 520 patents of invention, wherein Fig. 3 can be described as " the asymmetric consequent converter of semibridge system (Half bridge asymmetrical buck converter) ", Fig. 4 can be described as " the asymmetric consequent converter of full-bridge type (Full bridge symmetrical buckconverter) ", because all outer auxiliary induction La (auxiliary inductor) that is equal to its transformer leakage inductance that is added with of this two circuit, therefore when reaching zero potential switching effect, this transformer does not have the problem of abnormal heating, but between the stray capacitance at the elementary winding two ends of this auxiliary induction La and this transformer, produced ring (ringing) phenomenon that can not be ignored, because this ringing current is vibration back and forth on the winding of inductor and transformer, to produce the effect of induction heating (induction heating) to the magnetic stamen, cause its efficient worsens thereupon, in addition, this parasitic oscillation is except meeting increases the EMI interference signal, also can be reflected to this Secondary winding of transformer, the withstand voltage of this secondary commutation part need to be improved more than 1.5 times at least, and this is the many shortcomings that cause because of ring on the asymmetric consequent converter of bridge-type of Imbertson.As shown in Figure 4, the circuit that is Imbertson on the elementary winding and secondary winding of transformer, the ringing that is produced.

2, flyback zero potential commutation circuit (Flyback Zero-Voltage Switching PowerConverter):

As Fig. 6, shown in 7, be ChristoPher P.Henze and Hubert C.Martin, Jr. U.S. the 5th that gets permission in October, 1991,057, the circuit embodiments of No. 986 patents of invention, in this embodiment, owing to there is not the auxiliary induction that adds, therefore switch if desire to reach zero potential, need to strengthen the air gap of its transformer, the peak of primary magnetic galvanic current that makes this transformer is to peak value, reflexes to the load current of primary side greater than primary side, and this demand is identical with the patent of invention of Putrice R.Lethellier, can cause transformer to generate heat singularly equally, be head it off, need to strengthen the size of this transformer, to increase its heat-sinking capability.

As Fig. 8, shown in 9, be Wittenbreder, Jr. U.S. the 5th that gets permission in March nineteen ninety-five with Ernest H., 402, the circuit embodiments of No. 329 patents of invention, owing to be equipped with auxiliary induction among this embodiment, the peak of the primary magnetic galvanic current of its transformer is to peak value, need not to reflex to greater than primary side the load current value of primary side, can reach the effect that zero potential is switched easily, this auxiliary induction can be a leakage inductance when utilizing this transformer with loose commissure coiling, also can be an outer coilloading, but, no matter form in which way, the side effect that causes because of ring all can take place on the patent of this patent and aforementioned Imbertson.As shown in figure 10, be Wittenbreder, the circuit of Jr. and Ernest H. on the elementary winding and secondary winding of transformer, the ringing that is produced.

Because aforementioned existing power converter is when carrying out the zero potential switching, its power rectification switch (PowerRectifier Switches) switches the parasitic ring (Parasitic Ringing) that moment produced, the magnetic stamen has been produced the effect of induction heating (induction heating), cause it and on efficient improves, be subjected to great restriction, increased the interference signal of electromagnetic interference simultaneously, and the revers voltage impact higher to the generation of rectification part, the present invention is directed to these because of many shortcomings that ringing produced, the system that a kind of no ring zero potential that is applied to power converter of developing is switched, this technology is carried out in high efficiency and the highdensity zero potential handoff procedure at power converter, can can produce a L-C resonant circuit (inductance one capacitive resonance circuit) of vibration at its transformer primary, when beginning ringing takes place, make the short circuit current on its inductance, and the voltage on its electric capacity is lived in strangulation, effectively eradicate the parasitic ring that existing zero potential commutation circuit is produced, make it not be subjected to the influence of this parasitism ring.

Main purpose of the present invention is to provide a kind of no ring zero-potential switching method and transducer that is applied to power converter, it can avoid auxiliary induction and main transformer to produce the problem that electromagnetic interference signal disturbs because of parasitic oscillation, and effectively alleviate requirement to the withstand voltage amount (reverse voltagerating) of primary side rectification part, make Zero voltage switching circuit can reach higher energy conversion efficiency and power density, easier requirement simultaneously by international electromagnetic interference standard (International EMIregulations) with auxiliary induction.

Another object of the present invention is to provide a kind of no ring zero-potential switching method and transducer that is applied to power converter, it can prevent it to produce vibration, effectively avoid taking place ringing, the zero potential that reaches high efficiency, high density and low interference signal is switched purpose.

Another purpose of the present invention is to provide a kind of no ring zero-potential switching method and transducer that is applied to power converter, it can significantly improve power density, and the volume size of heat energy of being accumulated on the minimizing power switch pipe and required fin, make power converter be easier to be applied in the various miniaturization electronics products, exempted and do not had a resonance type zero potential commutation circuit of secondary inductor and realize zero potential because of the electric leakage sensibility reciprocal that too relies on transformer and switch, cause when design and manufacturing, be difficult for reaching its design specification, and be difficult to mass-produced shortcoming.

The objective of the invention is to realize by following technical solution: a kind of no ring zero-potential switching method that is applied to power converter, this method is a kind of at the zero potential commutation circuit on the power converter, in carrying out high efficiency and highdensity zero potential handoff procedure, understand the L-C circuit that produces vibration on the primary side of its transformer and the situation that ringing takes place, when ring begins to take place, with the short circuit current on the L-C circuit inductance, and the voltage method on its electric capacity is lived in strangulation.

The electric capacity of described L-C circuit is the stray capacitance on the primary side of this transformer; Described L-C circuit inductance is an auxiliary induction, and this inductance is set at the elementary winding of transformer and being connected in series between the contact of two power switch pipes; Described power switch pipe is a fet power pipe; On the elementary winding and the line contacts between auxiliary induction of described transformer, add at least one short circuit diode, when lc circuit begins to produce ring, these diodes are had an effect with corresponding power switch pipe respectively, electric current on the auxiliary induction is given short circuit, and the voltage on the stray capacitance is lived in strangulation.

A kind of half-bridge forward type does not have the power converter that the ring zero potential is switched full-wave rectification, and it comprises:

One input voltage filtering capacitor, the both positive and negative polarity of this input voltage filtering capacitor is connected across on the both positive and negative polarity of an input voltage, be parallel with two power switch pipes that are connected in series mutually on it, wherein the drain electrode of a power switch pipe is connected with the positive pole of input voltage filtering capacitor, source electrode is connected with the drain electrode of another power switch pipe, and the source electrode of another power switch pipe then is connected to the negative pole of input voltage filtering capacitor;

One transformer, this transformer is provided with an elementary winding and two level windings, one end of this elementary winding is connected with the negative pole of an electric capacity, its other end is connected to circuit between two power switch pipes by an auxiliary induction, the positive pole of this electric capacity is connected with the drain electrode of power switch pipe, link tester between this elementary winding and auxiliary induction is crossed two diodes, be connected respectively to the drain electrode of a power switch pipe and the source electrode of another power switch pipe, these diodes cooperate corresponding power switch pipe respectively, when circuit generation ringing, allow electric current on the auxiliary induction at once by the power switch pipe of correspondence and diode short circuit.

It also comprises the level winding two times, one end of these two level windings is connected to the negative pole of an output voltage filtering capacitor, its in addition end then be connected with the anode of the diode of two primary side respectively, the negative pole of the diode of these primary side then is connected by the positive pole of an inductance with the output voltage filtering capacitor, and this output voltage filtering capacitor provides the load of a stable VD to institute's cross-over connection on the output; Described power switch pipe is a fet power pipe.

A kind of half-bridge forward type that boosts does not have the power converter that the ring zero potential is switched full-wave rectification, and it comprises:

One input voltage filtering capacitor, the both positive and negative polarity of this input voltage filtering capacitor is connected across on the both positive and negative polarity of an input voltage, be parallel with two power switch pipes and an electric capacity of mutual serial connection on it, the negative pole of this electric capacity is connected with the positive pole of input voltage filtering capacitor, and the drain electrode of an anodal power switch pipe with wherein is connected; The source electrode of this power switch pipe is connected with the drain electrode of another power switch pipe, and the source electrode of another power switch pipe then is connected to the negative pole of input voltage filtering capacitor;

One transformer, this transformer is provided with an elementary winding, one end of this elementary winding is connected with the negative pole of above-mentioned electric capacity, its in addition end be connected to circuit between two power switch pipes by an auxiliary induction, circuit between this elementary winding and auxiliary induction is by two diodes, be connected respectively to the drain electrode of a power switch pipe and the source electrode of another power switch pipe, these diodes cooperate corresponding power switch pipe respectively, when this circuit generation ringing, make electric current on the auxiliary induction at once by the power switch pipe of correspondence and diode short circuit.

It also comprises the level winding two times, one end of these two level windings is connected to the negative pole of an output voltage filtering capacitor, its other end then is connected with the anode of the diode of two primary side respectively, the negative terminal of the diode of these primary side is then by an inductance, be connected with the positive pole of this output voltage filtering capacitor, the output voltage filtering capacitor provides the load of a stable VD to institute's cross-over connection on the output; Described power switch pipe is a fet power pipe.

A kind of half-bridge forward type does not have the power converter that the ring zero potential is switched halfwave rectifier, and it comprises:

One input voltage filtering capacitor, the both positive and negative polarity of this input voltage filtering capacitor is connected across on the both positive and negative polarity of an input voltage, be parallel with two power switch pipes that are connected in series mutually on it, wherein the drain electrode of a power switch pipe is connected with the positive pole of this input voltage filtering capacitor, its source electrode is connected with the drain electrode of another power switch pipe, and the source electrode of another power switch pipe then is connected to the negative pole of input voltage filtering capacitor;

One transformer, this transformer is provided with an elementary winding, one end of this elementary winding is connected with the negative pole of an electric capacity, the other end is connected to circuit between two power switch pipes by an auxiliary induction, the positive pole of this electric capacity is connected with the drain electrode of power switch pipe, link tester between elementary winding and auxiliary induction is crossed a diode, be connected to the drain electrode of power switch pipe, this diode cooperates power switch pipe, when circuit generation ringing, allow electric current on the auxiliary induction at once by power switch pipe and diode short circuit.

It also comprises the level winding one time, one end of this secondary winding is connected respectively to the anode of a diode of primary side and the negative pole of an output voltage filtering capacitor in regular turn, the other end then passes through another diode and an inductance of primary side in regular turn, be connected with the positive pole of output voltage filtering capacitor, the negative terminal of the diode of this primary side then is connected to another diode of primary side and the circuit between the output voltage filtering capacitor; Described power switch pipe is a fet power pipe.

A kind of half-bridge forward type that boosts does not have the power converter that the ring zero potential is switched halfwave rectifier, and it comprises:

One input voltage filtering capacitor, the both positive and negative polarity of this input voltage filtering capacitor is connected across on the both positive and negative polarity of an input voltage, be parallel with two power switch pipes and an electric capacity of one group of serial connection on it, the negative pole of this electric capacity is connected with the positive pole of input voltage filter capacitor, the drain electrode of its anodal power switch pipe with wherein is connected, the source electrode of this power switch pipe is connected with the drain electrode of another power switch pipe, and the source electrode of this another power switch pipe then is connected to the negative pole of input voltage filtering capacitor;

One transformer, this transformer is provided with an elementary winding, one end of this elementary winding is connected with the negative pole of above-mentioned electric capacity, its other end is connected to circuit between two power switch pipes by an auxiliary induction, circuit between elementary winding and auxiliary induction is by a diode, is connected to the drain electrode of power switch pipe, and this diode cooperates power switch pipe, when circuit generation ringing, make on the auxiliary induction electric current at once by power switch pipe with the diode short circuit.

Its circuit also comprises the level winding one time, one end of this secondary winding is connected respectively to the anode of a diode of primary side and the negative pole of an output voltage filtering capacitor in regular turn, its other end then passes through another diode and an inductance of primary side in regular turn, be connected with the positive pole of output voltage filtering capacitor, the negative terminal of the diode of primary side then is connected to another diode of primary side and the circuit between the output voltage filtering capacitor; Described power switch pipe is a fet power pipe.

A kind of half-bridge returns magnetic-type does not have the power converter that the ring zero potential is switched, and it comprises:

One input voltage filtering capacitor, the both positive and negative polarity of this input voltage filtering capacitor is connected across on the both positive and negative polarity of an input voltage, be parallel with two power switch pipes that are connected in series mutually on it, wherein the drain electrode of a power switch pipe is connected with the positive pole of input voltage filtering capacitor, its source electrode is connected with the drain electrode of another power switch pipe, and the source electrode of this another power switch pipe then is connected to the negative pole of input voltage filtering capacitor;

One transformer, this transformer is provided with an elementary winding, one end of this elementary winding is connected with the negative pole of an electric capacity, the other end is respectively by an auxiliary induction and a diode, be connected to the circuit between two power switch pipes and the source electrode of another power switch pipe, this diode cooperates another power switch pipe, when circuit generation ringing, makes electric current on the auxiliary induction at once by another power switch pipe and diode short circuit.

It also comprises the level winding one time, one end of this secondary winding is by the diode of a primary side, be connected with the positive pole of an output voltage filtering capacitor, the other end then is connected with the negative pole of this output voltage filtering capacitor, and the output voltage filtering capacitor provides the load of a stable VD to institute's cross-over connection on the output; Described power switch pipe is a fet power pipe.

Half-bridge boosts and returns the power converter that magnetic-type does not have the switching of ring zero potential, and it comprises:

One input voltage filtering capacitor, the both positive and negative polarity of this input voltage filtering capacitor is connected across on the both positive and negative polarity of an input voltage, be parallel with two power switch pipes and an electric capacity of one group of serial connection on it, the negative pole of this electric capacity is connected with the positive pole of input voltage filtering capacitor, the drain electrode of its anodal power switch pipe with wherein is connected, the source electrode of this power switch pipe is connected with the drain electrode of another power switch pipe, and the source electrode of this another power switch pipe then is connected to the negative pole of input voltage filtering capacitor;

One transformer, this transformer is provided with an elementary winding, one end of this elementary winding is connected with the negative pole of above-mentioned electric capacity, its other end is connected to the circuit between two power switch pipes and the source electrode of a power switch pipe by an auxiliary induction and a diode respectively, this diode cooperates a power switch pipe, when this circuit generation ringing, make electric current on the auxiliary induction at once by a power switch pipe and diode short circuit.

It also comprises the level winding one time, one end of this secondary winding is by the diode of a primary side, be connected with the positive pole of output voltage filtering capacitor, its other end then is connected with the negative pole of this output voltage filtering capacitor, and this output voltage filtering capacitor provides the load of a stable VD to institute's cross-over connection on the output; Described power switch pipe is a fet power pipe.

Because the present invention is arranged on the auxiliary induction on the zero potential commutation circuit between the tandem link contact of the elementary winding of transformer and two fet power pipes, again at the elementary winding of transformer and add on the line contacts between inductor, add at least one diode respectively, when these diodes can power up sensor outside and begin to produce ring, respectively with corresponding power switch effect, electric current on the secondary inductor is given short circuit, and the voltage on the primary side stray capacitance of transformer is lived in strangulation, prevent it to produce vibration, effectively avoid taking place ringing, reach high efficiency, the zero potential of high density and low interference signal is switched purpose.

Because the present invention is arranged on the auxiliary induction on the zero potential commutation circuit between the tandem link contact of the elementary winding of transformer and two fet power pipes, again at the elementary winding of transformer and add on the line contacts between inductor, add at least one diode respectively, when these diodes can power up sensor outside and begin to produce ring, respectively with corresponding power switch pipe effect, electric current on the secondary inductor is given short circuit, and the voltage on the primary side stray capacitance of transformer is lived in strangulation, prevent it to produce vibration, effectively avoid taking place ringing, reach high efficiency, the zero potential of high density and low interference signal is switched purpose.

Because the present invention will not have the ring technology and will be applied to various flyback, on the power converter of boost type and buck, these power converters can effectively avoid taking place ringing, to switch under the operation at high frequency, effectively reduce power loss, significantly improve its power density, and the volume size of heat energy of being accumulated on the minimizing power switch pipe and required fin, make power converter be easier to be applied in the various miniaturization electronics products, exempted and do not had a resonance type zero potential commutation circuit of secondary inductor and realize zero potential because of the electric leakage sensibility reciprocal that too relies on transformer and switch, cause when design and manufacturing, be difficult for reaching its design specification, and be difficult to mass-produced shortcoming.

Below in conjunction with drawings and Examples the present invention is done further detailed explanation.

Fig. 1 is the main circuit figure of the 383rd, No. 594 patent of invention of the U.S..

Fig. 2 is the main circuit figure of the 4th, 975, No. 821 patents of invention of the U.S..

Fig. 3 is the main circuit figure of the 5th, 245, No. 520 patents of invention of the U.S..

Fig. 4 is the main circuit figure of the 5th, 245, No. 520 patents of invention of the U.S..

Fig. 5 is the parasitic ringing schematic diagram that the patent circuit of Imbertson is produced.

Fig. 6 is the main circuit figure of the 5th, 057, No. 986 patents of invention of the U.S..

Fig. 7 is the main circuit figure of the 5th, 057, No. 986 patents of invention of the U.S..

Fig. 8 is the main circuit figure of the 5th, 402, No. 329 patents of invention of the U.S..

Fig. 9 is the main circuit figure of the 5th, 402, No. 329 patents of invention of the U.S..

Figure 10 is Wittenbreder, the schematic diagram of the parasitic ringing that the patent circuit of Jr. and Ernest H. is produced.

Figure 11 is the circuit diagram of first specific embodiment of the present invention.

The parasitic ringing schematic diagram that Figure 12 is produced when no ring suppresses circuit for Figure 11 does not add.

One of Figure 13 oscillogram schematic diagram that parasitic ring disappeared when no ring suppressed circuit for Figure 11 adds.

Two of Figure 14 oscillogram schematic diagram that parasitic ring disappeared when no ring suppressed circuit for Figure 11 adds.

Figure 15 is divided into one of equivalent circuit diagram of 10 periods for Figure 11.

Figure 16 be divided into for Figure 11 10 periods equivalent circuit diagram two.

Figure 17 be divided into for Figure 11 10 periods equivalent circuit diagram three.

Figure 18 be divided into for Figure 11 10 periods equivalent circuit diagram four.

Figure 19 be divided into for Figure 11 10 periods equivalent circuit diagram five.

Figure 20 be divided into for Figure 11 10 periods equivalent circuit diagram six.

Figure 21 be divided into for Figure 11 10 periods equivalent circuit diagram seven.

Figure 22 be divided into for Figure 11 10 periods equivalent circuit diagram eight.

Figure 23 be divided into for Figure 11 10 periods equivalent circuit diagram nine.

Figure 24 be divided into for Figure 11 10 periods equivalent circuit diagram ten.

Figure 25 one of schemed for the period of underarm ring clamped circuit of the present invention.

Figure 26 is two of the period figure of underarm ring clamped circuit of the present invention.

Figure 27 is three of the period figure of underarm ring clamped circuit of the present invention.

Figure 28 is the voltage and the current waveform figure of underarm ring clamped circuit of the present invention.

Figure 29 one of schemed for the period of upper arm ring clamped circuit of the present invention.

Figure 30 is two of the period figure of upper arm ring clamped circuit of the present invention.

Figure 31 is three of the period figure of upper arm ring clamped circuit of the present invention.

Figure 32 is the voltage and the current waveform figure of upper arm ring clamped circuit of the present invention.

Figure 33 is the result map that the specific embodiment of Figure 11 of the present invention is obtained on efficient.

Figure 34 is the result map that the specific embodiment of Figure 11 of the present invention is obtained on electromagnetic interference.

Figure 35 is the circuit diagram of second specific embodiment of the present invention.

Figure 36 is the circuit diagram of the 3rd specific embodiment of the present invention.

Figure 37 is the circuit diagram of the 4th specific embodiment of the present invention.

Figure 38 is the circuit diagram of the 5th specific embodiment of the present invention.

Figure 39 is the circuit diagram of the 6th specific embodiment of the present invention.

The system that the present invention is switched for a kind of no ring zero potential that is applied to power converter, this technology is at the zero potential commutation circuit on the power converter, in carrying out high efficiency and highdensity zero potential handoff procedure, can produce a L-C resonant circuit of vibration on the primary side of its transformer, when it begins ring takes place, with the short circuit current on its inductance, and strangulation lives the voltage on its electric capacity, thereby effectively eradicates the parasitic ring that the zero potential commutation circuit is produced.

The present invention will have the zero potential commutation circuit of have auxiliary induction on the power converter (auxiliary Inductor) and balancing capacitance (balance capacitor) now, again do an arrangement, secondary inductor on the zero potential commutation circuit is arranged on the elementary winding of transformer and being connected in series between the contact of two fet power pipes, again at the elementary winding of transformer and add on the line contacts between inductor, add a short circuit diode, or add two short circuit diodes, this adds the formed L-C circuit of stray capacitance (stray capacitance) on the primary side of secondary inductor and transformer, when beginning to produce ring, these diodes can be had an effect with corresponding power switch pipe respectively, the electric current that adds on the inductor is given short circuit, and the voltage on the primary side stray capacitance of transformer is lived in strangulation, to prevent it to produce vibration, effectively avoid taking place ringing, reach high efficiency, the zero potential of high density and low interference signal is switched purpose.

As shown in figure 11, be first specific embodiment of the present invention, it is applied to no ring zero potential handoff technique of the present invention in the design of one half-bridge forward type full-wave rectifying circuit, can be referred to as " the half-bridge forward type does not have the ring zero potential and switches full-wave rectifying circuit (Half-Bridge Forward Ring-FreeZero-Voltage-Switching Full-Wave Converter) " at this.In this embodiment, circuit comprises an input voltage filtering capacitor Cin, the both positive and negative polarity of this capacitor Cin is connected across on the both positive and negative polarity of an input voltage vin, be parallel with power switch pipe Q1, the Q2 of one group of serial connection on it, the drain electrode of this power switch pipe Q2 is connected with the positive pole of capacitor Cin, its source electrode is connected with the drain electrode of this power switch pipe Q1, the source electrode of this power switch pipe Q1 then is connected to the negative pole of capacitor Cin, and this capacitor Cin can provide a stable input voltage to use to a transformer.This transformer is mainly used to store and discharge electric energy, which is provided with an elementary winding Np and two level winding Ns1, Ns2, and its inductance value is respectively Lp and Ls1, Ls2, and the mark on the winding as shown in figure 11; The end of elementary winding Np is connected with the negative pole of a balancing capacitance Cb, its other end is connected to two power switch pipe Q1 by an auxiliary induction La, circuit between Q2, the positive pole of this capacitor C b then is connected with the drain electrode of power switch pipe Q2, in this embodiment, link tester between elementary winding Np and auxiliary induction La is crossed diode D4 and D3, be connected respectively to the drain electrode of power switch pipe Q2 and the source electrode of Q1, this diode D4 (or D3) can cooperate power switch pipe Q2 (or Q1) respectively, when circuit generation ringing, make on the auxiliary induction La current i la at once by power switch pipe Q2 with diode D4 (or power switch pipe Q1 and diode D3) short circuit, to stop ringing; The end of two level winding Ns1, Ns2 is connected to the negative pole of an output voltage filtering capacitor Co, its other end then is connected with the anode of diode D1, D2 respectively, the negative terminal of diode D1, D2 then is connected with the positive pole of capacitor Co by an inductance L o, and capacitor Co can provide a stable VD Vo load to institute's cross-over connection on the output.

For highlighting the influence that aforementioned ringing causes, can be earlier from embodiment shown in Figure 11, remove and be used for two diode D3 and the D4 of shorts inductor La, after this circuit working is stable, utilize an oscilloscope again, measure the oscillogram of its voltage and electric current, as shown in figure 12, can learn easily by this oscillogram, after ringing appears at time t3 and t8.Again diode D3 and D4 reinstall are put, at identical measurement point measured voltage and current waveform figure, then as shown in figure 13, by this oscillogram as can be known, behind time t3 and t8, though ringing still takes place in beginning, during to time t4 and t9, promptly lived, occur very slight remained shock again up to time t5 and t10 beginning by strangulation.Hence one can see that, the present invention is directed among this embodiment to produce the L-C circuit of vibration, utilizes two diodes, and the electric current on its inductance is given short circuit, can strangulation lives the voltage on its electric capacity, and prevent it to produce vibration, effectively avoids taking place ringing.

For specifying among this embodiment power switch pipe Q1 and Q2 when each conducting, can interact with two diode D3 and D4 respectively, live the principle of ring with strangulation, the spy is with oscillogram amplification shown in Figure 13 and be distinguished into 10 periods, as shown in figure 14, and again among Figure 15-24, the equivalent circuit diagram that shows these 10 periods respectively, in these circuit diagrams, thick line is partly represented the circuit of working in the circuit, and on behalf of the circuit of not working in the circuit, dotted line, fine rule partly then partly represent the variable condition of circuit circuit can be by the zero potential conducting time, now, be described in detail as follows with regard to the operating state of day part circuit:

1, the t10-t1 period:

Equivalent electric circuit as shown in figure 15, this period and last period are all being transmitted energy.In this period, power switch pipe Q1 and diode D1 are conducting state, and electric current is flowed into by the anode of input Vin, behind balancing capacitance Cb, elementary winding Np, auxiliary induction La and power switch pipe Q1, flows to the negative terminal of input Vin; At this moment, be recharged, also be recharged at the inductance L o and the capacitor C o of primary side at the balancing capacitance Cb and the auxiliary induction La of primary side.

2, the t1-t2 period:

Equivalent electric circuit as shown in figure 16, this period can be by the resonance phase of zero potential conducting chance for power switch pipe Q2.When time t1, power switch pipe Q1 is opened a way, the equivalent inductance Lnp of auxiliary induction La and transformer primary will form a L-C resonance trough (L-C tank) with parasitic capacitance CQ1, the CQ2 on power switch pipe Q1, the Q2, and the current i La on the auxiliary induction La is the initial current of resonance during with time ti, begin respectively to charge to parasitic capacitance CQ1 and CQ2, this resonance will make power switch pipe Q2 obtain the possibility that zero potential is switched.When the voltage on the elementary winding Np is kept to zero, diode D2 begins conducting, with the also interaction of the diode D1 in conducting, Secondary winding of transformer has been formed short-circuit condition, because the help of auxiliary induction La, parasitic capacitance CQ1 and CQ2 could continue to be recharged, when exceeding Vin etc. the voltage Vds on the capacitor C Q1, parasitic diode DQ2 is switched on, and promptly having formed power switch pipe Q2 can be by the chance of zero potential conducting.

3, the t2-t3 period:

Equivalent electric circuit as shown in figure 17, this period is gone up the phase that turns to of electric current ila for auxiliary induction La.In this period, diode D1 and D2 all are in conducting state, and therefore, elementary winding Np goes up and no-voltage, at this moment, because parasitic diode DQ2 and all conductings of power switch pipe Q2, make the voltage on the auxiliary induction La equal the voltage Vcb of capacitor C b, the slope of current i cb is-Vcb/La, when this current i La also be on the occasion of the time, expression capacitor C b just is recharged, and when current i La becomes negative value, represents that promptly capacitor C b begins to be discharged.

4, the t3-t4 period:

Equivalent electric circuit as shown in figure 18, this period is the formation phase of upper arm ring (ringing in upper side).When time t3, because the discharge of capacitor C b, voltage on the elementary winding Np changes negative by zero, make diode D1 quilt against ending partially, auxiliary induction La just forms a resonance trough with the stray capacitance Cnp of transformer primary, at this moment, if there is not diode D4, stray capacitance CNp will be discharged and recharged, and ringing occurs.

5, the t4-t5 period:

Equivalent electric circuit as shown in figure 19, this period is the short circuit phase of upper arm ringing current.In this period, D1 is cut off beginning from diode, voltage Vd3 just rises rapidly, when exceeding input terminal voltage Vin (during time t4) Deng voltage Vd3, diode D4 is switched on, electric current on the auxiliary induction La at once by power switch pipe Q2 with diode D4 short circuit, ringing promptly thereby stop to have realized that upper arm does not have the target of ring (ringfree in upper side); During equal time t5 because the electric current on the diode D4 has been not enough to allow diode D4 conducting again, so the energy on the auxiliary induction La is only enough to form very slight remained shock, and unlikely circuit is constituted influence.

6, the t5-t6 period:

Equivalent electric circuit as shown in figure 20, this period and last period are energy and transmit the phase.In this period, power switch pipe Q2 and diode D2 all are in conducting state, electric current is flowed out by the anode of capacitor C b, behind power switch pipe Q2, auxiliary induction La and elementary winding Np, flow back to the negative terminal of capacitor C b, at this moment, the energy on the capacitor C b will be via the transformer commissure to secondary-side circuitry, and, inductance L o and capacitor C o are charged through diode D2.

7, the t6-t7 period:

Equivalent electric circuit as shown in figure 21, this period can be by the resonance phase of zero potential conducting chance for forming power switch pipe Q1.When time t6, power switch pipe Q2 is opened a way, equivalent inductance LNp on auxiliary induction La and the primary winding will form a L-C resonance trough (L-Ctank) with parasitic capacitance CQ1, CQ2, and be the initial current of resonance with the current i La on the 6 o'clock time auxiliary induction La, begin respectively parasitic capacitance CQ1, CQ2 are discharged, this resonance will make power switch pipe Q1 thereby obtain the possibility that zero potential is switched.When the voltage on the elementary winding Np is kept to zero, diode D1 begins conducting, with the also interaction of the diode D2 in conducting, Secondary winding of transformer has been formed short-circuit condition, because the help of auxiliary induction La, parasitic capacitance CQ1 and CQ2 could continue to be discharged, when hanging down the zero crossing position etc. the voltage Vds on the parasitic capacitance CQ1, parasitic current potential DQ1 is switched on, and promptly having formed power switch pipe Q1 can be by the chance of zero potential conducting.

8, the t7-t8 period:

Equivalent electric circuit as shown in figure 22, this period is gone up the phase that turns to of electric current iLa for auxiliary induction La.In this period, diode D1 and D2 all are in conducting state, and therefore, elementary winding Np goes up and no-voltage, at this moment, because parasitic diode DQ1 and all conductings of power switch pipe Q1 make that the voltage on the auxiliary induction La equals the poor Vin-Vcb between voltage Vcb on input terminal voltage Vin and the capacitor C b, the slope of current i La is (Vin-Vcb)/La, when this current i La also is negative value, expression capacitor C b is just discharged, when current i La become on the occasion of the time, represent that promptly capacitor C b begins to be recharged.

9, the t8-t9 period:

Equivalent electric circuit as shown in figure 23, this period is the formation phase of underarm ring (ringing in lower side).When time t8, because capacitor C b is recharged, voltage on the elementary winding Np is become a full member by zero, make diode D2 quilt against ending partially, the stray capacitance CNp that auxiliary induction La satisfies with transformer primary forms a resonance trough, at this moment, if there is not diode D3, stray capacitance CNp will be discharged and recharged, and ringing occurs.

10, the t9-t10 period:

Equivalent electric circuit as shown in figure 24, this period is the short circuit phase of underarm ringing current.In this period, D2 is cut off from diode, voltage Vd3 just descends rapidly, Deng voltage Vd3 low zero potential (when being time t9), diode D3 just is switched on, electric current on the auxiliary induction La at once by power switch pipe Q1 with diode D3 short circuit, ringing promptly thereby stop to have realized that underarm does not have the target of ring (Ring free inlower side); During equal time t10, because the electric current on the diode D3 has been not enough to make diode D3 conducting again, so the energy on the auxiliary induction La is only enough to form very slight remained shock, and unlikely to the influence of circuit formation.

As shown in the above description, during the period, the ringing current that can make upper arm is by short circuit at t4-t5 for this embodiment, and during the period, the ringing current that can make underarm is by short circuit at t9-t10, and so, this embodiment can carry out zero potential and switch under the situation of no ring smoothly.

In addition, by above stated specification as can be known, the ringing effect that general power converter is produced when using the zero potential handoff technique, can generally be divided into two kinds of underarm ring and upper arm rings, the present invention just suppresses the principle and the advantage thereof of this two ringing effect again, cooperate the equivalent electric circuit shown in Figure 25-33, labor is described as follows:

A, the repressed principle of underarm ring and advantage thereof:

(1), at t7-t8 in the period:

Equivalent electric circuit as shown in figure 25, this period is gone up the phase that turns to of electric current iLa for auxiliary induction La.In this period, since time t7, transformer is by diode D2 and D1 short circuit, current i La on the auxiliary induction La is rapidly to rising, during to time t7a, current i La by negative value change on the occasion of, after being t8 to the time, this current i La is because the open circuit of diode D2, and changes the slope that relaxes with, continues to rise.

(2), the t8-t9 period:

Equivalent electric circuit as shown in figure 26, this period is the initial phase of underarm ring.For convenience of description, be the voltage and the current waveform figure of underarm ring clamped circuit as shown in figure 28, wherein the current i La on the auxiliary induction La can be divided into two partly, is denoted as the electric current part for the transformer primary of flowing through of ip, its size is only relevant with load, does not influence the behavior of ring; Be denoted as being respectively of iCs and iD3 flow through the stray capacitance CS of primary side and diode D3 electric current partly, its size is irrelevant, only relevant with ring with load.When the time is t8, diode D2 open circuit, the short circuit of transformer is removed, stray capacitance Cs on auxiliary induction La and the transformer primary, form the L-C resonance trough, and with V (La)=Vin-VCb, V (Cs＞0) is initial conditions, begin resonance, because stray capacitance Cs begins to be recharged, the voltage Vd3 on the diode D3 descends rapidly, when dropping to negative value, diode D3 is switched on, and the resonance current on the auxiliary induction La by diode D3 and power switch pipe Q1 short circuit, has been prevented the ring that will take place at once.When the time was t9, the energy of being accumulated on stray capacitance Cs and the auxiliary induction La was identical, is:

E(Cs)＝E(La)＝1/2*Cs(Vin-VCb)*(Vin-VCb) (1)

(3), the t9-t10 period:

Equivalent electric circuit as shown in figure 27, in this period, the underarm ring is prevented.If the ring end prevented by diode D3, and during resonance undamped (damping ratio=0), the voltage of the stray capacitance Cs on the transformer primary can be filled to 2 times of Vin-VCb, make stray capacitance Cs be accumulated to maximum energy, and its value is:

E(Cs)＝1/2*Cs[2(Vin-VCb)]*[2(Vin-VCb)] (2)

Again, if ring do not prevented by diode D3, but when being added with RC antihunt circuit (RC sunbbercircuit) on the circuit, the ceiling capacity that is accumulated on the stray capacitance Cs should be exhausted by the RC antihunt circuit, could exempt the influence of ring fully.After the underarm ring was prevented by diode D3, the energy that auxiliary induction La is accumulated to when time t9 will be at t9-t10 in the period, and D3 exhausts by diode.Calculate that thus because the underarm ring is prevented, the consume of circuit will reduce, the consume that it reduced is that formula (2) deducts formula (1), obtains:

Consume=3/2Cs (Vin-VCb) * (Vin-VCb) (3) that reduces

As can be known from the above analysis, this embodiment is adding no ring technology of the present invention behind its underarm, can reduce 3/4ths because the energy loss that the underarm ring is brought.

B, the repressed principle of upper arm ring and advantage:

The repressed principle of upper arm ring is identical with the repressed principle of underarm ring basically, but the energy of being saved is inequality, is described in detail as follows:

(1), the t2-t3 period:

Equivalent electric circuit as shown in figure 29, this period is gone up the phase that turns to of electric current iLa for auxiliary induction La.In this period, since time t2, transformer is by diode D1 and D2 short circuit, and the current i La on the auxiliary induction La descends rapidly, during to time t2a, electric current is by on the occasion of changing into negative value, be t3 to the time after, this electric current is because diode D1 open circuit, and changes the slope that relaxes with, continues to descend.

(2), the t3-t4 period:

Equivalent electric circuit as shown in figure 30, this period is the initial phase of ring.For convenience of description, be the voltage and the current waveform figure of upper arm ring clamped circuit shown in figure 32, wherein the current i La on the auxiliary induction La can be divided into two partly, is denoted as the electric current part for the transformer primary of flowing through of 1p, its size is only relevant with load, does not influence the behavior of ring; Be denoted as the electric current part of iCs and iD4, its size is irrelevant, only relevant with ring with load.When the time is t3, diode D1 open circuit, the short circuit of transformer is removed, stray capacitance Cs on auxiliary induction La and the transformer primary, form the L-C resonance trough, and with V (La)=Vin, V (Cs)=0 is initial conditions, begin resonance, because stray capacitance Cs begins to be recharged, the voltage Vd3 on the diode D3 is rapidly toward rising, be raised to input voltage vin when above, diode D4 is switched on, and the resonance current on the auxiliary induction La by diode D4 and power switch pipe Q2 short circuit, has been prevented the ring that will take place at once.When the time was t4, the energy of being accumulated on stray capacitance Cs and the auxiliary induction La was identical, is:

E(Cs)＝E(La)＝1/2VCb*VCb (4)

(3), the t4-t5 period:

Equivalent electric circuit as shown in figure 31, in this period, the upper arm ring is prevented.If ring give to be prevented by D4, and during resonance undamped (damoing ratio=0), the voltage of the stray capacitance Cs on the transformer primary can be filled to 2 times of VCb, make stray capacitance Cs be accumulated to maximum energy, and its value is:

E(Cs)＝2Cs*VCb*VCb (5)

Again, if ring do not prevented by diode D4, but when being added with RC antihunt circuit (RC snubbercircuit) on the circuit, the ceiling capacity that is accumulated on the stray capacitance Cs should be exhausted by the RC antihunt circuit, could exempt the influence of ring fully.After the upper arm ring was prevented by diode D4, the energy that auxiliary induction La is accumulated at time t4 will be at t4-t5 in the period, and D4 exhausts by diode.Calculate that thus because the upper arm ring is prevented, the consume of circuit will reduce, the consume that it reduced is that formula (5) deducts formula (4) and obtains:

Loss=the 3/2Cs*VCb*VCb (6) that reduces

As can be known from the above analysis, this embodiment is adding no ring technology of the present invention thereon behind the arm, can reduce 3/4ths because the energy loss that the upper arm ring is brought.

Add up to formula (2) to be the gross energy loss that the underarm ring brings with formula (5):

* (the Vin-VCb)+VCb*VCb of ring total losses=2Cs[(Vin-VCb)] (7)

Add up to formula (1) and formula (4) to be the underarm ring when all being suppressed, the gross energy loss that brings:

* (the Vin-VCb)+VCb*VCb of no ring total losses=1/2Cs[(Vin-VCb)] (8)

In this embodiment, if the stray capacitance Cs on this transformer primary is 100pF, input voltage vin is 400V, voltage VCb on the capacitor C b is 100V, then the ring of this power converter is when consuming with the RC antihunt circuit, its gross energy loss is 20 little joules (uJ), energy loss during no ring is 5.0 little joules, so each energy dissipation that reduces is 15 little joules during no ring, at this moment, if this power converter is worked under the frequency of 100KHZ, then the power loss of RC antihunt circuit is 2.0 watts, power loss during no ring is 0.5 watt, so the power dissipation during no ring has reduced 1.5 watts.Again, if its operating frequency rises to 200KHZ, then the power loss of RC antihunt circuit is 4.0 watts, and the power loss during no ring is 1.0 watts, so the power dissipation during no ring will reduce 3.0 watts.Hence one can see that, the loss that ring caused, operating frequency with circuit increases progressively, this also is the design and the manufacturer of conventional power converter, when its zero potential commutation circuit of design, can't break through the major reason of its maximum operating frequency all the time, this obstacle is after adding no ring mechanism of the present invention, owing to can effectively reduce the energy loss that causes because of ring, so can significantly promote the operating frequency of zero potential commutation circuit and the power density of power converter.

As shown in figure 33, the achievement that on efficient, is obtained for the embodiment of Figure 11 of the present invention, input voltage vin is the direct current of 370V in this embodiment, output voltage V out is 12V/5A, and operating frequency is 60KHZ, and the inductance L P on the elementary winding of main transformer is 1.2mH, leakage inductance is 4.5uH, adding auxiliary induction La is 35uH, and the 1st curve subdued ring with the RC antihunt circuit among the figure, so efficient only reaches 91%.Article 2, curve is under the condition of work that is same as the 1st curve, but the diode D3 and the D4 that change to add suppressed ringing eliminate ring, owing to do not have the consumption of antihunt circuit, its improved efficiency to 92%.Article 3, curve is under the condition of work that is same as the 2nd curve, because no ring, so with the rectifier diode of primary side, using instead withstand voltage is 100 volts, forward pressure drop Vf is 0.65 volt a Schottky diode, its efficient general thereby be promoted to 94% again.

As shown in figure 34, be the achievement of Figure 11 embodiment of the present invention on the electromagnetic interference interference signal, wherein last figure is the frequency spectrum when ring is arranged, the frequency spectrum of figure below during for no ring, near 2.5MHZ, the improvement of the 6dB that has an appointment, in fact, 2.5MHZ approximately be exactly the frequency of ring, after ring is suppressed, on frequency spectrum, just can't see interference signal certainly.

Second specific embodiment of the present invention, no ring zero potential handoff technique of the present invention is applied to a half-bridge to boost in the design of forward type full-wave rectifying circuit, as shown in figure 35, can be referred to as " half-bridge boost forward type do not have the ring zero potential switch full-wave rectifying circuit (Half-bridge Boost Forward Ring-Free Zero-Voltage-Switching Full-Wave Converter) " at this.In this embodiment, this circuit comprises an input voltage filtering capacitor Cin, the both positive and negative polarity of this capacitor Cin is connected across on the both positive and negative polarity of an input voltage vin, be parallel with power switch pipe Q1, Q2 and a capacitor C b of one group of serial connection on it, the negative pole of capacitor C b is connected with the positive pole of capacitor C in, its positive pole is connected with the drain electrode of power switch pipe Q2, the source electrode of power switch pipe Q2 is connected with the drain electrode of power switch pipe Q1, the source electrode of power switch pipe Q1 then is connected to the negative pole of capacitor Cin, and capacitor Cin can provide a stable input voltage to use to transformer.Transformer is provided with an elementary winding Np and two level winding Ns1, Ns2, and the mark on the winding as shown in figure 35; The end of this elementary winding Np is connected with the negative pole of capacitor C b, it is held in addition and is connected to two power switch pipe Q1 by an auxiliary induction La, circuit between Q2, in this embodiment, link tester between elementary winding Np and auxiliary induction La is crossed diode D4 and D3, be connected respectively to the drain electrode of power switch pipe Q2 and the source electrode of Q1, diode D4 (or D3) can cooperate this power switch pipe Q2 (or Q1) respectively when this circuit generation ringing, make on the auxiliary induction La current i La at once by power switch pipe Q2 with diode D4 (or power switch pipe Q1 and diode D3) short circuit, to stop this ringing; The circuit connecting mode of these two level winding NS1, NS2 is then identical with the secondary-side circuitry of first embodiment.

The 3rd specific embodiment of the present invention, no ring zero potential handoff technique of the present invention is applied in the design of a half-bridge forward type half-wave rectifying circuit, as shown in figure 36, can be referred to as " the half-bridge forward type does not have the ring zero potential and switches half-wave rectifying circuit (Half-Bridge Forward Ring-Free Zero-Voltage-Switching Half-Wave Converter) " at this.In this embodiment, this circuit comprises an input voltage filtering capacitor Cin, the both positive and negative polarity of capacitor Cin is connected across on the both positive and negative polarity of an input voltage vin, be parallel with power switch pipe Q1, the Q2 of one group of serial connection on it, the drain electrode of power switch pipe Q2 is connected with the positive pole of capacitor Cin, its source electrode is connected with the drain electrode of this power switch pipe Q1, and the source electrode of power switch pipe Q1 then is connected to the negative pole of capacitor Cin, and capacitor Cin can provide a stable input voltage to use to transformer.Transformer is provided with an elementary winding Np and a level winding Ns, and the mark on the winding as shown in figure 38; The end of this elementary winding Np is connected with the negative pole of a capacitor C b, it is held in addition and is connected to two power switch pipe Q1 by an auxiliary induction La, circuit between Q2, the positive pole of capacitor C b then is connected with the drain electrode of power switch pipe Q2, in this embodiment, link tester between elementary winding Np and auxiliary induction La is crossed diode D4, be connected to the drain electrode of power switch pipe Q2, diode D4 can cooperate power switch pipe Q2, when this circuit generation ringing, make on the auxiliary induction La current i La at once by power switch pipe Q2 with diode D4 short circuit, to stop ringing; The end of secondary winding Ns is connected respectively to the anode of a diode D2 and the negative pole of an output voltage filtering capacitor Co in regular turn, it is held in addition then in regular turn by a diode D1 and an inductance L o, be connected with the positive pole of capacitor Co, the negative terminal of diode D2 then is connected to the circuit between diode D1 and capacitor Co.Because this embodiment utilizes halfwave rectifier, so its ringing effect occurs over just D1 when being cut off, therefore need add diode D4, can realize not having the purpose of ring.

The 4th specific embodiment of the present invention, no ring zero potential handoff technique of the present invention is applied to a half-bridge to boost in the design of forward type half-wave rectifying circuit, as shown in figure 37, can be referred to as " half-bridge boost forward type do not have the ring zero potential switch half-wave rectifying circuit (Half-Bridge Boost Forward Ring-Free Zero-Voltage-Switching Half-Wave Converter) " at this.In this embodiment, circuit comprises an input voltage filtering capacitor Cin, the both positive and negative polarity of this capacitor Cin is connected across on the both positive and negative polarity of an input voltage vin, be parallel with power switch pipe Q1, Q2 and a capacitor C b of one group of serial connection on it, the negative pole of capacitor C b is connected with the positive pole of capacitor C in, its positive pole is connected with the drain electrode of power switch pipe Q2, the source electrode of power switch pipe Q2 is connected with the drain electrode of power switch pipe Q1, the source electrode of power switch pipe Q1 then is connected to the negative pole of capacitor Cin, and capacitor Cin can provide a stable input voltage to use to transformer.This transformer is provided with an elementary winding Np and a level winding Ns, mark on the winding as shown in figure 37, the end of this elementary winding Np is connected with the negative pole of capacitor C b, it is held in addition and is connected to two power switch pipe Q1 by an auxiliary induction La, circuit between Q2, in this embodiment, link tester between this elementary winding Np and auxiliary induction La is crossed a diode D4, be connected to the drain electrode of power switch pipe Q2, diode D4 can cooperate power switch pipe Q2, when this circuit generation ringing, make on the auxiliary induction La current i La at once by power switch pipe Q2 with diode D4 short circuit, to stop ringing: the circuit connecting mode of secondary winding Ns is then identical with the secondary-side circuitry of the 3rd embodiment.Because this embodiment utilizes halfwave rectifier, so its ringing effect occurs over just D1 when being cut off, therefore need add diode D4, can realize not having the purpose of ring.

The 5th specific embodiment of the present invention, no ring zero potential handoff technique of the present invention is applied to a half-bridge to be returned in the design of magnetic-type commutation circuit, as shown in figure 38, can be referred to as " half-bridge returns magnetic-type does not have ring zero potential commutation circuit (Half-Bridge Flyback Ring-Free Zero-VoltageSwitching Converter) " at this.In this embodiment, circuit comprises an input voltage filtering capacitor Cin, the both positive and negative polarity of this capacitor Cin is connected across on the both positive and negative polarity of an input voltage vin, be parallel with power switch pipe Q1, the Q2 of one group of serial connection on it, the drain electrode of this power switch pipe Q2 is connected with the positive pole of capacitor Cin, its source electrode is connected with the drain electrode of power switch pipe Q1, and the source electrode of power switch pipe Q1 then is connected to the negative pole of capacitor Cin, and capacitor Cin can provide a stable input voltage to use to transformer T1.This transformer T1 is provided with an elementary winding Np and a level winding Ns, and the mark on the winding as shown in figure 38; The end of elementary winding Np is connected with the negative pole of a capacitor C b, it is held in addition respectively by an auxiliary induction La and a diode D3, be connected to two power switch pipe Q1, the source electrode of circuit between Q2 and power switch pipe Q1, in this embodiment, because the circuit between elementary winding Np and auxiliary induction La is by diode D3, be connected to the source electrode of power switch pipe Q1, so diode D3 can cooperate power switch pipe Q1, when this circuit generation ringing, make on the auxiliary induction La current i La at once by power switch pipe Q1 with diode D3 short circuit, to stop ringing; The end of secondary winding Ns is connected with the positive pole of an output voltage filtering capacitor Co by a diode D1, its in addition end then be connected with the negative pole of capacitor Co, capacitor Co can provide a stable VD Vo load to institute's cross-over connection on the output.Because this embodiment utilizes halfwave rectifier, so its ringing effect occurs over just D1 when being cut off, therefore need add diode D3, can realize not having the purpose of ring.

The 6th specific embodiment of the present invention, no ring zero potential handoff technique of the present invention is applied to half-bridge to boost and returns in the design of magnetic-type commutation circuit, as shown in figure 39, also can be referred to as " half-bridge boost return magnetic-type do not have ring zero potential commutation circuit (Half-Bridge Boost Flyback Ring-FreeZero-Voltage-Switching Converter) " at this.In this embodiment, circuit comprises an input voltage filtering capacitor Cin, the both positive and negative polarity of this capacitor Cin is connected across on the both positive and negative polarity of an input voltage vin, be parallel with power switch pipe Q1, Q2 and a capacitor C b of one group of serial connection on it, the negative pole of this capacitor C b is connected with the positive pole of capacitor C in, its positive pole is connected with the drain electrode of power switch pipe Q2, the source electrode of power switch pipe Q2 is connected with the drain electrode of power switch pipe Q1, the source electrode of power switch pipe Q1 then is connected to the negative pole of capacitor Cin, and capacitor Cin can provide a stable input voltage to use to transformer.This transformer T1 is provided with an elementary winding Np and a level winding Ns, mark on the winding as shown in figure 39, the end of this elementary winding Np is connected with the negative pole of capacitor C b, its in addition end be connected to circuit between two power switch pipe Q1, Q2 and the source electrode of power switch pipe Q1 by an auxiliary induction La and a diode D3 respectively; In this embodiment, because the circuit between elementary winding Np and auxiliary induction La is by diode D3, be connected to the source electrode of power switch pipe Q1, so diode D3 can cooperate power switch pipe Q1, when this circuit generation ringing, make on the auxiliary induction La current i La at once by power switch pipe Q1 with diode D3 short circuit, to stop ringing; The circuit connecting mode of two level windings is then identical with the secondary-side circuitry of the 5th embodiment.Because this embodiment utilizes halfwave rectifier, so its ringing effect occurs over just D1 when being cut off, therefore need add diode D3, can realize not having the purpose of ring.

According to the above, utilize no ring zero potential handoff technique of the present invention, can make power converter under high frequency environment, carry out zero potential and switch operation, avoid auxiliary induction to produce the problem of abnormal heating because of parasitic oscillation, effectively reduce power loss, and effectively alleviate requirement to the withstand voltage amount (reversevoltage rating) of primary side rectification part, significantly promote its operating frequency and power density, and the interference signal of minimizing electromagnetism, and the heat energy accumulated of power switch pipe and the volume size of required fin, make power converter be easy to standard, and be easier to be applied in the design of various miniaturization electronics products by international electromagnetic interference.

Claims

1, a kind of no ring zero-potential switching method that is applied to power converter, it is characterized in that: this method is at the zero potential commutation circuit on the power converter for a kind of, in carrying out high efficiency and highdensity zero potential handoff procedure, understand the L-C circuit that produces vibration on the primary side of its transformer and the situation that ringing takes place, when ring begins to take place, with the short circuit current on the L-C circuit inductance, and the voltage method on its electric capacity is lived in strangulation.

2, the no ring zero-potential switching method that is applied to power converter as claimed in claim 1 is characterized in that: the electric capacity of described L-C circuit is the stray capacitance on the primary side of this transformer.

3, the no ring zero-potential switching method that is applied to power converter as claimed in claim 1, it is characterized in that: described L-C circuit inductance is an auxiliary induction, and this inductance is set at the elementary winding of transformer and being connected in series between the contact of two power switch pipes.

4, the no ring zero-potential switching method that is applied to power converter as claimed in claim 3, it is characterized in that: described power switch pipe is a fet power pipe.

5, as claim 2, the 3 or 4 described no ring zero-potential switching methods that are applied to power converter, it is characterized in that: on the elementary winding and the line contacts between auxiliary induction of described transformer, add at least one short circuit diode, when lc circuit begins to produce ring, these diodes are had an effect with corresponding power switch pipe respectively, electric current on the auxiliary induction is given short circuit, and the voltage on the stray capacitance is lived in strangulation.

6, a kind of half-bridge forward type does not have the power converter that the ring zero potential is switched full-wave rectification, and it is characterized in that: it comprises:

7, half-bridge forward type as claimed in claim 6 does not have the power converter that the ring zero potential is switched full-wave rectification, it is characterized in that: it also comprises the level winding two times, one end of these two level windings is connected to the negative pole of an output voltage filtering capacitor, its in addition end then be connected with the anode of the diode of two primary side respectively, the negative pole of the diode of these primary side then is connected by the positive pole of an inductance with the output voltage filtering capacitor, and this output voltage filtering capacitor provides the load of a stable VD to institute's cross-over connection on the output.

8, do not have the power converter that the ring zero potential is switched full-wave rectification as claim 6 or 7 described half-bridge forward types, it is characterized in that: described power switch pipe is a fet power pipe.

9, a kind of half-bridge forward type that boosts does not have the power converter that the ring zero potential is switched full-wave rectification, and it is characterized in that: it comprises:

10, the half-bridge as claimed in claim 9 forward type that boosts does not have the power converter that the ring zero potential is switched full-wave rectification, it is characterized in that: it also comprises the level winding two times, one end of these two level windings is connected to the negative pole of an output voltage filtering capacitor, its other end then is connected with the anode of the diode of two primary side respectively, the negative terminal of the diode of these primary side is then by an inductance, be connected with the positive pole of this output voltage filtering capacitor, the output voltage filtering capacitor provides the load of a stable VD to institute's cross-over connection on the output.

11, do not have the power converter that the ring zero potential is switched full-wave rectification as claim 9 or the 10 described half-bridges forward type that boosts, it is characterized in that: described power switch pipe is a fet power pipe.

12, a kind of half-bridge forward type does not have the power converter that the ring zero potential is switched halfwave rectifier, and it is characterized in that: it comprises:

13, half-bridge forward type as claimed in claim 12 does not have the power converter that the ring zero potential is switched halfwave rectifier, it is characterized in that: it also comprises the level winding one time, one end of this secondary winding is connected respectively to the anode of a diode of primary side and the negative pole of an output voltage filtering capacitor in regular turn, the other end then passes through another diode and an inductance of primary side in regular turn, be connected with the positive pole of output voltage filtering capacitor, the negative terminal of the diode of this primary side then is connected to another diode of primary side and the circuit between the output voltage filtering capacitor.

14, do not have the power converter that the ring zero potential is switched halfwave rectifier as claim 12 or 13 described half-bridge forward types, it is characterized in that: described power switch pipe is a fet power pipe.

15, the half-bridge forward type that boosts does not have the power converter that the ring zero potential is switched halfwave rectifier, and it is characterized in that: it comprises:

16, the half-bridge as claimed in claim 15 forward type that boosts does not have the power converter that the ring zero potential is switched halfwave rectifier, it is characterized in that: its circuit also comprises the level winding one time, one end of this secondary winding is connected respectively to the anode of a diode of primary side and the negative pole of an output voltage filtering capacitor in regular turn, its other end then passes through another diode and an inductance of primary side in regular turn, be connected with the positive pole of output voltage filtering capacitor, the negative terminal of the diode of primary side then is connected to another diode of primary side and the circuit between the output voltage filtering capacitor.

17, do not have the power converter that the ring zero potential is switched halfwave rectifier as claim 15 or the 16 described half-bridges forward type that boosts, it is characterized in that: described power switch pipe is a fet power pipe.

18, half-bridge returns magnetic-type does not have the power converter that the ring zero potential is switched, and it is characterized in that: it comprises:

19, half-bridge as claimed in claim 18 returns magnetic-type does not have the power converter that the ring zero potential is switched, it is characterized in that: it also comprises the level winding one time, one end of this secondary winding is by the diode of a primary side, be connected with the positive pole of an output voltage filtering capacitor, the other end then is connected with the negative pole of this output voltage filtering capacitor, and the output voltage filtering capacitor provides the load of a stable VD to institute's cross-over connection on the output.

20, return the power converter that magnetic-type does not have the switching of ring zero potential as claim 18 or 19 described half-bridges, it is characterized in that: described power switch pipe is a fet power pipe.

21, half-bridge boosts and returns the power converter that magnetic-type does not have the switching of ring zero potential, and it is characterized in that: it comprises:

22, half-bridge as claimed in claim 21 boosts and returns the power converter that magnetic-type does not have the switching of ring zero potential, it is characterized in that: it also comprises the level winding one time, one end of this secondary winding is by the diode of a primary side, be connected with the positive pole of output voltage filtering capacitor, its other end then is connected with the negative pole of this output voltage filtering capacitor, and this output voltage filtering capacitor provides the load of a stable VD to institute's cross-over connection on the output.

23, boost as claim 21 or 22 described half-bridges and return magnetic-type and do not have the power converter that the ring zero potential is switched, it is characterized in that: described power switch pipe is a fet power pipe.