CN203377803U - Full-bridge AC-DC conversion apparatus - Google Patents
Full-bridge AC-DC conversion apparatus Download PDFInfo
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- CN203377803U CN203377803U CN201320286649.5U CN201320286649U CN203377803U CN 203377803 U CN203377803 U CN 203377803U CN 201320286649 U CN201320286649 U CN 201320286649U CN 203377803 U CN203377803 U CN 203377803U
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Abstract
A full-bridge AC-DC conversion apparatus includes a filter circuit, four switch blocks, a first capacitor, a second capacitor and a first inductance. The filter circuit is connected with a power supply; each switch block includes an active switch and a diode, and the diode is in parallel connection with the active switch; the first capacitor and the first inductor comprise a resonant circuit; and the second capacitor is in parallel connection with a load. When switch blocks are switched, the structure of the whole circuit is automatically changed, and a better filtering effect is obtained.
Description
Technical field
The utility model is relevant with AC-DC conversion; Refer to especially a kind of full-bridge type DC-AC conversion device.
Background technology
The full-bridge type AC/DC changeover switch mostly adopts the high frequency switching mode to produce pulse width modulation (Pulse Width Modulation, PWM) signal and splits to close and carry out the rigidity switching, to control electrical energy flows through different paths, and then reaches the effect of AC-DC conversion.And aforesaid way often can produce a large amount of higher harmonic currents, and then disturb other equipment.Therefore, the selection of the wave filter on AC side of full-bridge type AC/DC changeover switch and design become quite important.
Therefore in general, compare traditional L-type filter, in the situation that same inductance value, the LCL mode filter is even more ideal to the high-frequency harmonic inhibition, has been applied to gradually on the device of high-power, low switching frequency.And the processing of traditional LC L signal that filter circuit adopts is as design concept with three rank filters.In other words, be to provide a low impedance path by the high frequency composition that wherein an inductance and electric capacity are output waveform, and then reduce the radio-frequency component of the electric current of another inductance of flowing through.Yet although, LCL mode filter filtering high order harmonic component successful, the design process of LCL mode filter is loaded down with trivial details and need to repeatedly attempt, checking computations just can be found suitable parameter repeatedly.In addition, because its circuit characteristic of LCL mode filter is subject to parameter influence, therefore be difficult for and other circuit integrated designs.
In addition, general full-bridge type DC-AC conversion device, in order to reduce cost of parts and to reduce the transducer volume, often can utilize the raising switching frequency to reduce the size of electric capacity and magnetic element.But promote the switching frequency of change-over circuit, relatively also increase the switch cost of switch element, also increase electromagnetic interference (EMI) problem simultaneously.Therefore that the design of existing full-bridge type AC/DC changeover switch is not attained yet is perfect, and the part that still haves much room for improvement.
The utility model content
In view of this, the purpose of this utility model is to provide a kind of full-bridge type DC-AC conversion device, has the effect of low electromagnetic interference (EMI), low ripple output voltage and high conversion efficiency.
Edge is to reach above-mentioned purpose, and after the utility model provides the full-bridge type DC-AC conversion device to convert direct current in order to the alternating current by a power supply, a load is given in power supply, and this load has a first end and one second end.This full-bridge type DC-AC conversion device includes a filter circuit, four switches set, one first electric capacity, one second electric capacity and one first inductance.Wherein, this filter circuit has an input side and an outlet side, and this input side and this power supply are electrically connected, and this output includes one first output and one second output.Described switches set is respectively one first switches set, a second switch group, one the 3rd switches set and one the 4th switches set, and distinctly include an active switch and a diode, this diode and this active switch in parallel, and the negative pole of this diode forms a first end of each switches set, and the positive pole of this diode forms one second end of each switches set; Wherein, the first output of the second end of this first switches set and this filter circuit is electrically connected; The first end of the first end of this second switch group and this first switches set is electrically connected, and the second output of the second end of this second switch group and this filter circuit is electrically connected; The first output of the second end of the first end of the 3rd switches set and this first switches set and this filter circuit is electrically connected, and the second end of the second end of the 3rd switches set and this load is electrically connected; The second output of the second end of the first end of the 4th switches set and this second switch group and this filter circuit is electrically connected, and the second end of the second end of the second end of the 4th switches set and the 3rd switches set and this load is electrically connected.The first end of this first electric capacity one end and this second switch group is electrically connected, and the other end is electrically connected with the first end of this load.The first end of this second electric capacity one end and this load is electrically connected, and the second end of the other end and this load is electrically connected.The first end of this first inductance one end and this second switch group is electrically connected, and the other end is electrically connected with the first end of this load.
Wherein, this filter circuit includes one second inductance, one the 3rd inductance and one the 3rd electric capacity; This second inductance one end and this power supply one end are electrically connected; The other end of the 3rd inductance one end and this second inductance is electrically connected, and the other end of the 3rd inductance forms this first output; The 3rd electric capacity one end is electrically connected between this second inductance and the 3rd inductance, and the other end is electrically connected and forms this second output with this power supply other end.
Wherein, this filter circuit includes one second inductance; This second inductance one end and this power supply one end are electrically connected, and the other end forms this first output; The other end of this power supply forms this second output.
Wherein, this first electric capacity is polarity free capacitor.
Wherein, this second electric capacity is non-electrolytic capacitor.
Wherein, the 3rd electric capacity is polarity free capacitor.
Wherein, this active switch is transistor.
Wherein, this active switch is mos field effect transistor (MOSFET).
Thus, by above-mentioned design, while carrying out AC-DC conversion, will produce the effect of low electromagnetic interference (EMI), low ripple output voltage and high conversion efficiency.
The accompanying drawing explanation
For further disclosing concrete technology contents of the present utility model, below in conjunction with embodiment and accompanying drawing, be described in detail as follows, wherein:
The circuit diagram of the full-bridge type DC-AC conversion device that Fig. 1 is preferred embodiment;
The equivalent circuit diagram that Fig. 2 to Fig. 7 is each step;
The mode chart that Fig. 8 is input voltage, electric current and output voltage.
Embodiment
For being illustrated more clearly in the utility model, enumerating preferred embodiment and coordinate accompanying drawing to be described in detail as follows.Refer to Fig. 1, after the full-bridge type DC-AC conversion device of the utility model one preferred embodiment converts direct current in order to the alternating current by a power supply 100, a load 200 is given in power supply, and this load 200 has a first end 201 and one second end 202.This full-bridge type DC-AC conversion device includes four switches set 11-14, one first capacitor C 1, one second capacitor C 2, one first inductance L 1 and a filter circuit 20.Wherein:
Described switches set 11-14 is respectively one first switches set 11, a second switch group 12, one the 3rd switches set 13 and one the 4th switches set 14, distinctly include an active switch S 1-S4 and a diode D1-D4, in the present embodiment, this active switch S 1-S4 is a mos field effect transistor (MOSFET), certainly also other transistor or other active switch elements on the implementation.The positive pole of this diode D1-D4 and the source electrode of this mos field effect transistor are electrically connected, negative pole is electrically connected with the drain of this mos field effect transistor, and makes this diode D1-D4 respectively and corresponding this active switch S 1-S4 parallel connection.In addition, the negative pole of this diode D1-D4 forms the first end of each switches set 11-14, and the positive pole of this diode D1-D4 forms one second end of each switches set 11-14.Respectively this switches set 11-14 annexation is as follows, and the first end of the first end of this first switches set 11 and this second switch group 12 is electrically connected.The second end of the first end of the 3rd switches set 13 and this first switches set 11 is electrically connected, and the second end 202 of the second end of the 3rd switches set 13 and this load 200 is electrically connected.The second end of the first end of the 4th switches set 14 and this second switch group 12 is electrically connected, and the second end 202 of the second end of the second end of the 4th switches set 14 and the 3rd switches set 13 and this load 200 is electrically connected.
This first capacitor C 1 is a polarity free capacitor, and the electric connection of the first end of an end and this second switch group 12, and the other end is electrically connected with the first end 201 of this load 200.This second capacitor C 2 is non-electrolytic capacitor, and first end 201 electric connections of an end and this load 200, and the second end 202 of the other end and this load 200 is electrically connected.The first end of these the first inductance L 1 one ends and this second switch group 12 is electrically connected, and the other end is electrically connected with the first end 201 of this load 200.
This filter circuit 20 has an input side 21 and an outlet side 22, and this input side 21 is electrically connected with this power supply 100, and this outlet side 22 is electrically connected with described switches set 11-14.In the present embodiment, this filter circuit 20 is LCL type filter circuit, and includes one second inductance L 2, one the 3rd inductance L 3 and one the 3rd capacitor C 3.These the second inductance L 2 one ends and this power supply 100 1 ends are electrically connected.The other end of the 3rd inductance L 3 one ends and this second inductance L 2 is electrically connected, and the other end of the 3rd inductance L 3 forms one first output 221, and is electrically connected between this first switches set 11 and the 3rd switches set 12.The 3rd capacitor C 3 one ends are electrically connected between this second inductance L 2 and the 3rd inductance L 3, the other end is electrically connected with these power supply 100 other ends, and form one second output 222, and be electrically connected between this second switch group 12 and the 4th switches set 14.
In the present embodiment, the resistance value of described capacitor C 1-C3, described inductance L 1-L3, input voltage, input voltage frequency, described switches set 11-14 switching frequency and this load 200 is as shown in the table:
| The |
220μH |
| The |
800μH |
| The |
120μH |
| The |
100μF |
| The |
2.2μF |
| The |
11nF |
| Input voltage V in | 110V rms |
| The input voltage frequency | 60Hz |
| Switching frequency | 100KHz |
| Load resistance | 500 |
Thus, by said structure, design and specification, recycle following power conversion method, just can reach the effect of low electromagnetic interference (EMI), low ripple output voltage and high conversion efficiency, and the method includes the following step, and the difference that is positive half wave or negative half-wave according to these power supply 100 electric energy, and distinguish to some extent:
Refer to Fig. 2 to Fig. 4, when these power supply 100 electric energy are positive half wave, this power conversion method comprises the following step:
A-1 as shown in Figure 2, active switch S 3, the S4 of conducting the 3rd switches set 13 and the 4th switches set 14, and end active switch S 1, the S2 of this first switches set 11 and this second switch group 12.Now, the electric energy of this power supply 100 gives the 3rd capacitor C 3 through these the second inductance L 2 transmission, the circuit that the 3rd capacitor C 3 forms by conducting the 3rd switches set 13 and the 4th switches set 14 is to the 3rd inductance L 3 energy storage, and makes this first inductance L 1 and this first capacitor C, 1 resonance.In addition, the negative voltage characteristic produced by this first inductance L 1 and this first capacitor C 1 resonance, diode D1, D2 by this first switches set 11 of conducting with this second switch group 12, circuit structure is changed, and produce circuit structure after the diode D1 of active switch S 3, S4 and this first switches set 11 by the 3rd switches set 13 and the 4th switches set 14 and this second switch group 12, D2 conducting, electric energy is sent to this second capacitor C 2 accumulation of energys, and gives by these the second capacitor C 2 power supplies the effect that this load 200 reaches the attenuating output ripple.
A-2 as shown in Figure 3, active switch S 1, the S4 of this first switches set of conducting 11 and 14 groups, the 4th switch, and end active switch S 2, the S3 of this second switch group 12 and the 3rd switches set 13.Now, the electric energy of this power supply 100 gives the 3rd capacitor C 3 through these the second inductance L 2 transmission, the circuit that the energy storage of the 3rd capacitor C 3 and the 3rd inductance L 3 forms by this first switches set 11 of conducting and the 4th switches set 14 is sent to this first capacitor C 1 and carries out accumulation of energy with resonant circuit and this second capacitor C 2 of this first inductance L 1, with power supply, gives this load 200 and reaches the effect that lowers output ripple.
A-3 as shown in Figure 4, when the energy storage of the 3rd inductance L 3 of this filter circuit 20 is made zero, continue active switch S 1, the S4 of this first switches set 11 of conducting and the 4th switches set 14, and end active switch S 2, the S3 of this second switch group 12 and the 3rd switches set 13.Now, the electric energy of this power supply 100 continues to be sent to the 3rd capacitor C 3 by this second inductance L 2, and this first inductance L 1 starts resonance generation negative supply characteristic with this first capacitor C 1, and the diode D2 of this second switch group 12 of conducting and the 3rd switches set 13, D3, circuit structure is changed, and by the active switch S 1 of this first switches set 11 and the 4th switches set 14, S4, and the diode D2 of this second switch group 12 and the 3rd switches set 13, produce circuit structure after the D3 conducting, electric energy is sent to this second capacitor C 2 accumulation of energys, and give by these the second capacitor C 2 power supplies the effect that this load 200 reaches the attenuating output ripple.
In addition, steps A-1 of every execution, to steps A-3, completes the start in a cycle.Be with, when these power supply 100 electric energy are positive half wave, repeated execution of steps A-1 is to steps A-3 until this power supply power change is negative half-wave, and in execution step A-1 to steps A-3 o'clock, the mode with flexibility switching, conducting or end this first switches set 11 and the 3rd switches set 13, and in the mode of rigidity switching, conducting or end this second switch group 12 and the 4th switches set 14, to reach the effect of low electromagnetic interference (EMI) and high conversion efficiency.
Refer to Fig. 5 to Fig. 7, when these power supply 100 electric energy are negative half-wave, this power conversion method comprises the following step:
B-1 as shown in Figure 5, active switch S 1, the S2 of this first switches set of conducting 11 and this second switch group 12, and end active switch S 3, the S4 of the 3rd switches set 13 and the 4th switches set 14.Now, the electric energy of this power supply 100 gives the 3rd capacitor C 3 through these the second inductance L 2 transmission, the circuit that the 3rd capacitor C 3 forms by this first switches set of conducting 11 and this second switch group 12 is to the 3rd inductance L 3 energy storage, and makes this first inductance L 1 and this first capacitor C, 1 resonance.In addition, the negative voltage characteristic produced by this first inductance L 1 and this first capacitor C 1 resonance, diode D3, D4 by conducting the 3rd switches set 13 with the 4th switches set 14, circuit structure is changed, and produce circuit structure after the diode D3 of active switch S 1, S2 and the 3rd switches set 13 by this first switches set 11 and this second switch group 12 and the 4th switches set 14, D4 conducting, electric energy is sent to this second capacitor C 2 accumulation of energys, and gives by these the second capacitor C 2 power supplies the effect that this load 200 reaches the attenuating output ripple.
B-2 as shown in Figure 6, active switch S 2, the S3 of this second switch group of conducting 12 and the 3rd switches set 13, and end active switch S 1, the S4 of this first switches set 11 and the 4th switches set 14.Now, the electric energy of this power supply 100 gives the 3rd capacitor C 3 through these the second inductance L 2 transmission, the circuit that the energy storage of the 3rd capacitor C 3 and the 3rd inductance L 3 forms by this second switch group 12 of conducting and the 3rd switches set 13, be sent to this first capacitor C 1 and carry out accumulation of energy with resonant circuit and this second capacitor C 2 of this first inductance L 1, give this load 200 with power supply and reach the effect that lowers output ripple.
B-3 as shown in Figure 7, when the 3rd inductance L 3 energy storage of this filter circuit 20 are made zero, continue active switch S 2, the S3 of this second switch group 12 of conducting and the 3rd switches set 13, and end active switch S 1, the S4 of this first switches set 11 and the 4th switches set 14.Now, the electric energy of this power supply 100 continues to be sent to the 3rd capacitor C 3 by this second inductance L 2, and this first inductance L 1 starts resonance generation negative supply characteristic with this first capacitor C 1, and the diode D1 of this first switches set 11 of conducting and the 4th switches set 14, D4, circuit structure is changed, and by the active switch S 2 of this second switch group 12 and the 3rd switches set 13, S3, and the diode D1 of this first switches set 11 and the 4th switches set 14, produce circuit structure after the D4 conducting, electric energy is sent to this second capacitor C 2 accumulation of energys, and give by these the second capacitor C 2 power supplies the effect that this load 200 reaches the attenuating output ripple.
In addition, step B-1 of every execution, to step B-3, completes the start in a cycle.Be with, when these power supply 100 electric energy are negative half-wave, repeated execution of steps B-1 is to step B-3 until this power supply 100 power change are positive half wave, and when performing step B-1 to step B-3, the mode with flexibility switching, conducting or end this first switches set 11 and the 3rd switches set 13, and in the mode of rigidity switching, conducting or end this second switch group 12 and the 4th switches set 14, to reach the effect of low electromagnetic interference (EMI) and high conversion efficiency.
Thus, by the design of said structure and method, as seen from Figure 8, in the present embodiment, in input voltage V
inpeak value is about in the situation of 150V, the input current I of second inductance L 2 of flowing through
l2effect by LCL type filter circuit can effectively reduce the high frequency ripple, and output dc voltage V
outbe about in the situation of 250V, its waveform is tending towards smooth, and has the effect of low output voltage ripple, and then can avoid this second capacitor C shorter electrochemical capacitor in 2 useful lifes, to promote the useful life of this full-bridge type DC-AC conversion device.
In addition, on reality is implemented, filter circuit of the present utility model is except using LCL type filter circuit, also can use the L-type filter circuit (is that filter circuit only has an inductance, and this inductance one end and this power supply 100 1 ends are electrically connected, and the other end forms the first output 221) also can reach the purpose of this utility model.Moreover, the foregoing is only the better possible embodiments of the utility model, the variation of the equivalent structure that every application the utility model specification and claim are done, ought to be included in claim scope of the present utility model.
Claims (8)
1. a full-bridge type DC-AC conversion device, after converting the alternating current of a power supply to direct current, powers and give a load, and this load has a first end and one second end; It is characterized in that, this full-bridge type DC-AC conversion device includes:
One filter circuit, have an input side and an outlet side, and this input side and this power supply are electrically connected, and this output includes one first output and one second output;
Four switches set, be respectively one first switches set, a second switch group, one the 3rd switches set and one the 4th switches set, and distinctly include an active switch and a diode, this diode and this active switch in parallel, and the negative pole of this diode forms a first end of each switches set, and the positive pole of this diode forms one second end of each switches set; Wherein, the first output of the second end of this first switches set and this filter circuit is electrically connected; The first end of the first end of this second switch group and this first switches set is electrically connected, and the second output of the second end of this second switch group and this filter circuit is electrically connected; The first output of the second end of the first end of the 3rd switches set and this first switches set and this filter circuit is electrically connected, and the second end of the second end of the 3rd switches set and this load is electrically connected; The second output of the second end of the first end of the 4th switches set and this second switch group and this filter circuit is electrically connected, and the second end of the second end of the second end of the 4th switches set and the 3rd switches set and this load is electrically connected;
One first electric capacity, the first end of one end and this second switch group is electrically connected, and the other end is electrically connected with the first end of this load;
One second electric capacity, the first end of one end and this load is electrically connected, and the second end of the other end and this load is electrically connected; And
One first inductance, the first end of one end and this second switch group is electrically connected, and the other end is electrically connected with the first end of this load.
2. full-bridge type DC-AC conversion device according to claim 1, is characterized in that, wherein, this filter circuit includes one second inductance, one the 3rd inductance and one the 3rd electric capacity; This second inductance one end and this power supply one end are electrically connected; The other end of the 3rd inductance one end and this second inductance is electrically connected, and the other end of the 3rd inductance forms this first output; The 3rd electric capacity one end is electrically connected between this second inductance and the 3rd inductance, and the other end is electrically connected and forms this second output with this power supply other end.
3. full-bridge type DC-AC conversion device according to claim 1, is characterized in that, wherein, this filter circuit includes one second inductance; This second inductance one end and this power supply one end are electrically connected, and the other end forms this first output; The other end of this power supply forms this second output.
4. full-bridge type DC-AC conversion device according to claim 1, is characterized in that, wherein, this first electric capacity is polarity free capacitor.
5. full-bridge type DC-AC conversion device according to claim 1, is characterized in that, wherein, this second electric capacity is non-electrolytic capacitor.
6. according to the described full-bridge type DC-AC conversion device of claim 2 or 3, it is characterized in that, wherein, the 3rd electric capacity is polarity free capacitor.
7. full-bridge type DC-AC conversion device according to claim 1, is characterized in that, wherein, this active switch is transistor.
8. full-bridge type DC-AC conversion device according to claim 7, is characterized in that, wherein, this active switch is mos field effect transistor.
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201320286649.5U CN203377803U (en) | 2013-05-23 | 2013-05-23 | Full-bridge AC-DC conversion apparatus |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201320286649.5U CN203377803U (en) | 2013-05-23 | 2013-05-23 | Full-bridge AC-DC conversion apparatus |
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| CN203377803U true CN203377803U (en) | 2014-01-01 |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104184344A (en) * | 2013-05-23 | 2014-12-03 | 东林科技股份有限公司 | Full-bridge AC/DC conversion device and conversion method thereof |
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2013
- 2013-05-23 CN CN201320286649.5U patent/CN203377803U/en not_active Expired - Fee Related
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104184344A (en) * | 2013-05-23 | 2014-12-03 | 东林科技股份有限公司 | Full-bridge AC/DC conversion device and conversion method thereof |
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|---|---|---|---|
| C14 | Grant of patent or utility model | ||
| GR01 | Patent grant | ||
| CF01 | Termination of patent right due to non-payment of annual fee |
Granted publication date: 20140101 Termination date: 20170523 |
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| CF01 | Termination of patent right due to non-payment of annual fee |