CN1130003C - Double phase change inverter circuit - Google Patents
Double phase change inverter circuit Download PDFInfo
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- CN1130003C CN1130003C CN 98115853 CN98115853A CN1130003C CN 1130003 C CN1130003 C CN 1130003C CN 98115853 CN98115853 CN 98115853 CN 98115853 A CN98115853 A CN 98115853A CN 1130003 C CN1130003 C CN 1130003C
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Abstract
The present invention relates to an inverter circuit which is composed of a reversing switch of a primary inverter circuit of a transformer and a reversing switch of a secondary circuit of the transformer, wherein the reversing switch of a primary inverter circuit is connected with the reversing switch of a secondary circuit in a bridge type mode. The circuit of the present invention is mainly characterized in that a secondary coil of the transformer has four taps, and two pairs of reversing switches SW between every two taps form bridge type connection. During the working of the circuit, the reversing switch of a primary inverter circuit is selectively matched with the reversing switch of a secondary input circuit to carry out synchronously switching on/off to obtain the commutation of a primary inverter circuit and the synchronous commutation of a secondary output circuit, and thus, the purpose of high frequency inversion and low frequency output is realized.
Description
The present invention relates to a kind of combining with the commutation of transformer secondary output output circuit and realize the inverter circuit of straight----friendship inversion with the commutation of primary inverter circuit.Belong to the circuit that direct current power is converted to AC power output.
Inverter is a kind of electric equipment that direct current energy is transformed into Alternating Current Power Supply.It is widely used in various aspects such as electric machine speed regulation, computer power failure preemergency power supply and electric energy conversion.
Existing inverter generally is divided into square wave type by its output AC voltage waveform, the nearly sinusoidal waveform of stairstepping.
The principle of existing square wave type inverter circuit as shown in Figure 1, K switch 1a, K1b are the commutation operating switch among the figure.E is a dc power supply, the closure of its both positive and negative polarity in circuit is decided according to the requirement of used switching device K1a, K1b, D1, D2 are fly-wheel diode, the closure of its both positive and negative polarity in circuit is decided according to the closure of dc power supply E both positive and negative polarity in circuit, B is a transformer, and L1 is its elementary winding, and [1] end is the center tap terminal of L1, L2 is its secondary output winding, and RL is a load resistance.
Narrate the operation principle of prior art and the shortcoming of existence below in conjunction with accompanying drawing.
As Fig. 1, K1a, K1b were off state when circuit working began among the figure, and the beginning back connects in turn K1a, turn-offs K1a by certain beat; Connect K1b, turn-off K1b; Connect K1a, turn-off K1a.Circulation is always gone down, and just obtains a positive and negative continuous square waveform output voltage that the intermittent phase is arranged at output.Adjust switch connection and the ratio of turn-off time, can change the size of output voltage effective value.The operating frequency of sort circuit is consistent with the frequency of output AC voltage, and in 50Hz or low frequency when work more, the volume of transformer is big, Heavy Weight, efficient is lower, noise is bigger; Output voltage is a square wave, can produce harmful effect to some electric equipment and motor etc.; Decrease in efficiency can occur when driving the unbalanced load of positive and negative half-wave, heating can not be worked, even the phenomenon of damaging.
As Fig. 2, each switch is a phase-change switch among the figure.In the elementary winding L 1 of transformer B, [1] end is for centre cap, between 2 ends and [1] end the number of turn and [1] hold and 22 ends between the number of turn identical; Between the end of 3 ends and [1] between the number of turn and [1] end and 33 ends the number of turn identical, and 3 ends and [1] hold between the number of turn hold greater than 2 ends and [1] between the number of turn; Between the end of 4 ends and [1] between the number of turn and [1] end and 44 ends the number of turn identical, and 4 ends and [1] hold between the number of turn hold greater than 3 ends and [1] between the number of turn.All switches all were in off state when circuit working began, and the beginning back is connected K3a, turn-offed K3a; Connect K2a, turn-off K2a; Connect K1a, turn-off K1a; Connect K2a, turn-off K2a; Connect K3a, turn-off K3a; Connect K3b, turn-off K3b; Connect K2b, turn-off K2b; Connect K1b, turn-off K1b; Connect K2b, turn-off K2b; Connect K3b, turn-off K3b; Connect K3a, turn-off K3a...... and circulate down, just obtain the output voltage that difference that an amplitude connects with operating switch changes at output, this just is equivalent to the change of alternating voltage instantaneous value always.Increase the right quantity of operating switch in the circuit, when increasing the position of the right quantity of Transformer Winding L1 tap and each tap of choose reasonable, just can obtain nearly sinusoidal wave staircase waveform ac output voltage.Each switch is all in the direct current supply side in this circuit, and the switch working state of direct current supply side is controlled difficulty when working because of inverter, so the components and parts cost of sort circuit and manufacture difficulty are all bigger; Transformer is operated under the low frequency situation in addition, and its volume is big, Heavy Weight, efficient is lower, noise is bigger; Sort circuit decrease in efficiency can occur when driving the unbalanced load of positive and negative half-wave, heating can not be worked, even the phenomenon of damaging.
The objective of the invention is existing inverter circuit is proposed improved a kind of scheme.Circuit of the present invention is to make the elementary inversion of inverter circuit partly be operated in the high frequency state, to reduce volume of transformer, weight reduction, raising circuit conversion efficient, to reduce the circuit working noise; And at output by waveform combination, with the positive and negative synthetic required waveform of high frequency square wave group such as the nearly sinewave output of low frequency stairstepping on transformer secondary output limit.
The objective of the invention is to realize by following circuit: circuit structure comprises that transformer B primary circuit has two inversion commutation K switch 1a, K1b, and two sustained diode 1, D2 and the DC power supply E etc. that connect, transformer B secondary coil 18 has tap 1, tap 2, tap 3,4 four taps of tap, four phase-change switches of two couples between per two taps all are that bridge-type connects, (as the phase-change switch between tap 1 and the tap 25,6,7,8; Phase- change switch 7,8,11,12 between tap 2 and the tap 4), four pairs of phase-change switches 5,6; 7,8; 9,10; 11,12 every pair all be connected into headtotail, the head of phase- change switch 5,7,9,11 is connected together becomes whole inverter circuit output 15, the afterbody of phase- change switch 6,8,10,12 is connected together and becomes behind inductance 14 of series connection again between another output 13, two outputs 15 and 13 of whole inverter circuit and connect electric capacity 16 and load 17.
As Fig. 3, in transformer B, coil L1 is its elementary winding, and wherein the b end is the centre cap of winding L 1; Coil 18 is its secondary winding, coil 18 total taps 1, tap 2, tap 3,4 four taps of tap, and 2 numbers of turn of tap 1 and tap and tap 1 and 4 turn ratios of tap are N1=N12/N14=0.15 during coiling.3 numbers of turn of tap 1 and tap and tap 1 and 4 turn ratios of tap are N2=N13/N14=0.40.Tap 1 and tap 4 when connecing phase-change switch arrisdefect gating, the output voltage maximum is Um.And tap 1 and tap 2 when connecing phase-change switch arrisdefect gating, output voltage is N1UM=0.15Um.Have again tap 2 and tap 3 when connecing phase-change switch arrisdefect gating, output voltage is (N2-N1) Um=(0.4-0.15) Um=0.25Um.Again tap 1 and tap 3 when connecing phase-change switch arrisdefect gating, output voltage is N2Um=0.4Um.Also have tap 3 and tap 4 when connecing phase-change switch arrisdefect gating, output voltage is (1-N2) Um=(1-0.4) Um=0.6Um.Last tap 2 and tap 4 when connecing phase-change switch arrisdefect gating, output voltage is (1-N1) Um=(1-0.15) Um=0.85Um.At this moment circuit output end can produce totally 6 kinds of staircase waveforms that different voltages are formed by 0.15Um, 0.25Um, 0.40Um, 0.60Um, 0.85Um, Um.
When beginning, turn-offs circuit working all switches; The beginning back connects in turn K1a, 6,7 three switches by certain beat, turn-offs K1a, 6,7 three switches; Connect K1b, 5,8 three switches, turn-off K1b, 5,8 three switches; Connect K1a, 8,9 three switches, turn-off K1a, 8,9 three switches; Connect K1b, 7,10 3 switches, turn-off K1b, 7,10 3 switches; Connect K1a, 6,9 three switches, turn-off K1a, 6,9 three switches; Connect K1b, 5,10 3 switches, turn-off K1b, 5,10 3 switches; Connect K1a, 10,11 3 switches, turn-off K1a, 10,11 3 switches; Connect K1b, 9,12 3 switches, turn-off K1b, 9,12 3 switches, connect K1a, 8,11 3 switches, turn-off K1a, 8,11 3 switches; Connect K1b, 7,12 3 switches, turn-off K1b, 7,12 3 switches; Connect K1a, 6,11 3 switches, turn-off K1a, 6,11 3 switches; Connect K1b, 5,12 3 switches, turn-off K1b, 5,12 3 switches, connect K1a, 6,11 3 switches, turn-off K1a, 6,11 3 switches; Connect K1b, 5,12 3 switches, turn-off K1b, 5,12 3 switches, connect K1a, 8,11 3 switches, turn-off K1a, 8,11 3 switches; Connect K1b, 7,12 3 switches, turn-off K1b, 7,12 3 switches; Connect K1a, 10,11 3 switches, turn-off K1a, 10,11 3 switches; Connect K1b, 9,12 3 switches, turn-off K1b, 9,12 3 switches; Connect K1a, 6,9 three switches, turn-off K1a, 6,9 three switches; Connect K1b, 5,10 3 switches, turn-off K1b, 5,10 3 switches; Connect K1a, 8,9 three switches, turn-off K1a, 8,9 three switches; Connect K1b, 7,10 3 switches, turn-off K1b, 7,10 3 switches; Connect K1a, 6,7 three switches, turn-off K1a, 6,7 three switches; Connect K1b, 5,8 three switches, turn-off K1b, 5,8 three switches; By top duty cycle, just obtain at output the output AC voltage formed by 6 grades of ladders on half-wave; And then still by original beat order, connect K1a, 5,8 three switches, turn-off K1a, 5,8 three switches; Connect K1b, 6,7 three switches, turn-off K1b, 6,7 three switches; Connect K1a, 7,10 3 switches, turn-off K1a, 7,10 3 switches; Connect K1b, 8,9 three switches, turn-off K1b, 8,9 three switches, connect K1a, 5,10 3 switches, turn-off K1a, 5,10 3 switches; Connect K1b, 6,9 three switches, turn-off K1b, 6,9 three switches; Connect K1a, 9,12 3 switches, turn-off K1a, 9,12 3 switches; Connect K1b, 10,11 3 switches, turn-off K1b, 10,11 3 switches, connect K1a, 7,12 3 switches, turn-off K1a, 7,12 3 switches; Connect K1b, 8,11 3 switches, turn-off K1b, 8,11 3 switches; Connect K1a, 5,12 3 switches, turn-off K1a, 5,12 3 switches; Connect K1b, 6,11 3 switches, turn-off K1b, 6,11 3 switches, connect K1a, 5,12 3 switches, turn-off K1a, 5,12 3 switches; Connect K1b, 6,11 3 switches, turn-off K1b, 6,11 3 switches, connect K1a, 7,12 3 switches, turn-off K1 a, 7,12 3 switches; Connect K1b, 8,11 3 switches, turn-off K1b, 8,11 3 switches; Connect K1a, 9,12 3 switches, turn-off K1a, 9,12 3 switches; Connect K1b, 10,11 3 switches, turn-off K1b, 10,11 3 switches, connect K1a, 5,10 3 switches, turn-off K1a, 5,10 3 switches; Connect K1b, 6,9 three switches, turn-off K1b, 6,9 three switches; Connect K1a, 7,10 3 switches, turn-off K1a, 7,10 3 switches; Connect K1b, 8,9 three switches, turn-off K1b, 8,9 three switches; Connect K1a, 5,8 three switches, turn-off K1a, 5,8 three switches; Connect K1b, 6,7 three switches, turn-off K1b, 6,7 three switches; By this duty cycle, at the get back following half-wave of the output AC voltage formed by 6 grades of ladders of output; And then still get back at the beginning circulation in proper order, connect K1a, 6,7 three switches, turn-off K1a, 6,7 three switches by original beat; So circulation is gone down, and has just realized the output of staircase waveform ac converter.
Can find out that from the working condition of this circuit circuit inversion part operating frequency is 24 times of output AC electricity frequency.
This circuit can be used for the inconsistent load of positive and negative half-wave character use down under the alternating voltage, as the load of halfwave rectifier type.This moment, general inverter can cause that work is undesired because of the transformer magnetic saturation, and inversion efficiency descends, even infringement.But because of its operating characteristic, circuit can not only operate as normal, and inversion efficiency can not reduce during by this circuit supply.
Because of this circuit all is added with phase-change switch at primary inverter circuit and secondary alternating voltage output circuit both sides.Whether not only relevant with switch commutation operating state in the primary circuit its ac output voltage phase change is, also relevant with secondary output circuit commutation operating state.That is to say, during circuit working when the commutation simultaneously of primary and secondary both sides, the output AC voltage phase invariant; And only during the primary edge commutation, the output AC voltage phase change.Therefore can find out that it uses single phase change inverter circuit at present always very big difference is arranged with aforementioned, again according to the characteristics of its bilateral commutation, so be called double phase change inverter circuit.Because the switch commutation makes the voltage-phase commutation of elementary inversion and secondary output circuit in the circuit, so from the voltage waveform angle, claim that here this circuit is a double phase change inverter circuit.
This invention is narrated than the improvement of prior art on performance is existing in front, but is summarized as follows in the lump with the advantage that other is not narrated at this again:
1) the circuit inversion partly is operated in the HF switch state.Thereby can reduce volume of transformer, alleviate transformer weight, improve inversion efficiency, reduce operating noise.
2) circuit can be little, in light weight at high-frequency inversion, volume, output 50Hz or below the 50Hz even ultra-low frequency alternating voltage under the little situation of wave distortion.
3) the circuit output voltage waveform does not change because of the load size variation.
4) circuit can be used for the inconsistent load of positive and negative half-wave character use down under the alternating voltage, as the load of halfwave rectifier type.This moment, general inverter can cause that work is undesired because of the transformer magnetic saturation, and inversion efficiency descends, even infringement.But because of its operating characteristic, circuit can not only operate as normal, and inversion efficiency can not reduce during by this circuit supply.
5) circuit can be made in same inverter output frequency difference, the different alternating current of voltage easily, as is exportable 220V/50Hz alternating current, exportable again 110V/60Hz alternating current, also exportable multiple direct voltage.
6) can make can be with the inverter of two or more inverter parallel synchronous operations of being made by same circuits, to increase power output for circuit.And each inverter wherein can use separately.
The explanation of accompanying drawing drawing
Fig. 1 is the square waveform inverter circuit figure of prior art.
Fig. 2 is a kind of Step Wave Inverter Circuit figure of prior art.
Fig. 3 is a kind of double phase change inverter circuit figure of the present invention.
Fig. 4 is for being elementary inversion commutation K switch i with triode, making the circuit diagram of secondary output phase-change switch of bidirectional triode thyristor.
Fig. 5 is for being elementary inversion commutation K switch i with field effect transistor, making the circuit diagram of secondary output phase-change switch of 16 one-way SCRs.
Fig. 6 is for two groups of usefulness circuit diagram of making of combination of circuits as shown in Figure 5 together.
Below in conjunction with accompanying drawing for embodiment:
In actual applications, according to the difference of institute's employing phase-change switch device, it is multi-form that double phase change inverter circuit shown in Figure 3 is convertible into many kinds, below provides wherein several:
Fig. 4 circuit is to replace the elementary inversion commutation of Fig. 3 circuit K switch i with triode Qi, replaces the circuit diagram of the secondary output phase-change switch of Fig. 3 circuit with bidirectional triode thyristor.
Fig. 5 circuit is to replace the elementary inversion commutation of Fig. 3 circuit K switch i with field effect transistor Fi, replaces the circuit diagram of the secondary output phase-change switch of Fig. 3 circuit with one-way SCR.Two one-way SCRs that each target among this figure and anode are connected together quite with Fig. 3 in a switch in the output phase-change switch, a bidirectional triode thyristor among also suitable and Fig. 4 in the bidirectional triode thyristor.
Fig. 6 circuit is output voltage decline groove during no conversion work in the output waveform that is together become by two combination of circuits shown in Figure 5, the better circuit theory diagrams of output waveform continuity.Another arm forms the magnet short-cut path electric current with regard to conducting and damages the phase-change switch pipe in the time of need preventing that the arm from thoroughly not turn-offing when recommending arm or brachium pontis conversion work in the inverter circuit work, the two arm phase-change switch pipe conversion work discontinuous phases of ending that generally all were provided with in the circuit working are also referred to as Dead Time, in this time period, two arm phase-change switch pipes all turn-off.Hysteresis effect in the transformer work also can exert an influence in addition.These are stranded the plain distortion that all can cause output waveform, these factors are bigger to the output waveform influence in inverter circuit work of the present invention, it mainly is the groove that output voltage waveforms descends when having conversion work in output waveform, for addressing this problem, two identical inverter circuits can be combined, their drive clock pulse is differed certain phase place (0 °-180 °) synchronous operation, and closing of their output pulse widths made greater than the pulse period have a rest conversion in two inverter circuit work only the phase staggers mutually, and their output linked together, circuit is two Fig. 5 combination of circuits circuit diagram of circuit together as shown in Figure 6.Dotted line institute frame 1 among Fig. 6,2 is two picture groups, 5 inverter circuits, their shared power supply E, and the outlet side of their secondary output switches also connects load together, (but under this synchronous operation state inverter outlet side multimachine and connect also be of the present invention one big characteristics) like this in the work in the positive half cycle and negative half period waveform of output voltage waveforms, arbitrary moment all have at least 1 group of inverter circuit in running order in.Dotted line institute frame 1 Partial Inverse among Fig. 6 is set in the circuit working exchanges work and make pulsewidth and dotted line institute frame 2 Partial Inverse and exchange work and do the closing of pulsewidth, and both pulse settings differ a phase bit with wrong slotted zones synchronous operation greater than the pulse period.Like this, the output voltage waveforms after they synthesize is continuous low frequency staircase waveform.
As mentioned above, this inventive circuit can be made up of multiple switching device, and multiple type of attachment can be arranged.Although it is so, but this class circuit has much in common.
1) its primary all be connected to phase-change switch that one group or array be made up of elementary inversion commutation K switch i to or the phase-change switch bridge.And transformer secondary output all is connected to one group or array by the phase-change switch bridge of secondary output phase-change switch to forming.
2) transformer B secondary winding 18 each tap position are by each instantaneous corresponding voltage amplitude proportion decision of output waveform.
3) among the elementary inversion commutation K switch i or several and the secondary output phase-change switch or several cooperate synchronously and turn-off, connect in the circuit working, thereby realize the purpose of transformer B primary edge and the synchronous commutation of secondary side.
4) two or more same circuits can be combined into a circuit, the output of these circuit also connects load together, these circuit are synchronous operation work, the phase difference of output pulse be (0 °-180 °) between these circuit, the closing greater than the pulse period of the pulse duration that these circuit are exported.To realize improving output waveform, strengthen purposes such as power output.
Claims (1)
1, a kind of double phase change inverter circuit, circuit structure comprises transformer (B), primary circuit phase-change switch (K1a, K1b), fly-wheel diode (D1, D2) and DC power supply (E), it is characterized in that: transformer (B) secondary coil (18) has first tap (1), second tap (2), the 3rd tap (3), (4) four taps of the 4th tap, four phase-change switches of two couples between per two taps all are that bridge-type connects four pairs of phase-change switches (5,6; 7,8; 9,10; 11,12) every pair all is connected into headtotail, the head of a switch in the every pair of phase-change switch is connected together and becomes of whole inverter circuit output (15), the afterbody of another switch in the every pair of phase-change switch is connected together becomes another output (13) of whole inverter circuit behind the inductance of series connection again (14), between two outputs (15,13) and connect electric capacity (16) and load (17).
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 98115853 CN1130003C (en) | 1998-07-13 | 1998-07-13 | Double phase change inverter circuit |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 98115853 CN1130003C (en) | 1998-07-13 | 1998-07-13 | Double phase change inverter circuit |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN1241839A CN1241839A (en) | 2000-01-19 |
| CN1130003C true CN1130003C (en) | 2003-12-03 |
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Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN 98115853 Expired - Fee Related CN1130003C (en) | 1998-07-13 | 1998-07-13 | Double phase change inverter circuit |
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| CN (1) | CN1130003C (en) |
Families Citing this family (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103259434B (en) * | 2013-04-23 | 2015-04-29 | 盐城工学院 | Primary side single-phase bridge-subsidiary side three-phase bridge high frequency chain inverter and digital control system thereof and method thereof |
| CN104917385B (en) * | 2015-05-23 | 2018-01-12 | 深圳市飞天鹰科技有限公司 | A kind of noise reduction type isolation type high frequency square wave DC D/C powers |
| CN108418232A (en) * | 2018-03-28 | 2018-08-17 | 南京新联能源技术有限责任公司 | Phase-change switch short circuit automatic bypass device |
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1998
- 1998-07-13 CN CN 98115853 patent/CN1130003C/en not_active Expired - Fee Related
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| CN1241839A (en) | 2000-01-19 |
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