CN1115765C - Three-phase bridge-type rectifier - Google Patents

Three-phase bridge-type rectifier Download PDF

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Publication number
CN1115765C
CN1115765C CN 99106059 CN99106059A CN1115765C CN 1115765 C CN1115765 C CN 1115765C CN 99106059 CN99106059 CN 99106059 CN 99106059 A CN99106059 A CN 99106059A CN 1115765 C CN1115765 C CN 1115765C
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phase
phase bridge
rectifier
link capacitance
type rectifier
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CN 99106059
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CN1249561A (en
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朱贤龙
齐勇
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Ansheng Electric Co., Ltd., Shenzhen City
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Emerson Network Power Co Ltd
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Abstract

The present invention relates to a bridge type rectifying device which comprises a bridge type rectifier, a DC busbar capacitor connected with the bridge type rectifier, a reactance part connected between a power input end and the rectifier, and an intermediate circuit connected between the reactance part and the bus capacitor. Power factors are raised and input harmonic waves are reduced by the bridge type rectifying device. Thus, the harmonic content THD of input current at the time that input line current is greater than 16A is smaller than or equal to 15%, and the power factors above 60 % of a rated load can be above 95%. The bridge type rectifying device can effectively inhibit the interference of an external power supply and reduce the capacity requirements for DC busbar filtering capacitors.

Description

Three-phase bridge-type rectifier
The present invention relates to a kind of three-phase bridge-type rectifier, relate in particular to the three-phase bridge-type rectifier that a kind of PPFC (Passive Power Factor Correction) and harmonic wave suppress.
The three-phase bridge-type rectifier of prior art as shown in Figure 1, wherein, the three-phase electricity u in grid alternating current source, v, w are respectively by after the bridge rectifier diode group D1-D6 rectification, through dc bus filter inductance L 1Filtering is then to dc bus electrochemical capacitor C 1And C 2Load circuit is sent in charging again.In this conventional equipment, the power factor of circuit is generally below 92%, even strengthen dc bus filter inductance L 1Value, it is about 95% that power factor also can only reach, and if dc bus filter inductance L 1Value too big, cause it to lose practical value again.In addition, the harmonic content of the three-phase bridge-type rectifier of this prior art is also bigger than normal, for input current less than the device below the 16A, harmonic content is difficult to reach IEC EN61000-3-2 standard (IEC-International Electrotechnical Commission), and under the situation of input current greater than 16A, the harmonic content THD that the three-phase bridge-type rectifier of this prior art produces (total harmonic distortion amount) is generally greater than 30%, and power factor is generally below 90%.For in high-power electric drive system, the power factor of the three-phase bridge-type rectifier of prior art generally reaches about 87% only.If do not add the DC filtering inductance, then the power factor of the three-phase bridge-type rectifier of prior art generally has only about 62%, and harmonic content THD can be up to more than 70%.Power factor is on the low side and harmonic content is bigger than normal, electrical network has been caused bigger negative effect, comprise that mainly the power factor capacity utilance of electrical network that then makes on the low side descends, increase the loss of electrical network, harmonic wave is bigger than normal, and electrical network is produced harmonic pollution, causes voltage, current waveform distortion in the electrical network, influence the operate as normal of other electric equipment on the electrical network, even may cause damaging.
Therefore, need a kind of three-phase bridge-type rectifier that can improve power factor and reduce harmonic content.
The object of the present invention is to provide a kind of three-phase bridge-type rectifier that power factor can be improved effectively and suppress harmonic content.
In order to realize purpose of the present invention, three-phase bridge-type rectifier according to a preferred embodiment of the present invention comprises the dc-link capacitance that the three-phase bridge rectifier group is connected with pair of output with this rectifier group, wherein, this three-phase bridge-type rectifier also comprises the reactive components of the input that is connected to three-phase input power supply and three-phase rectifier group, and is connected the intermediate circuit of mainly being made up of three polarity free capacitors between the intermediate node of this reactive components and dc-link capacitance.They carry out filtering and improve power factor the input power supply, and harmonic wave is effectively suppressed.
According to a preferred embodiment of three-phase bridge-type rectifier of the present invention, reactive components can be a three-phase reactor, also can be three single-phase reactors.
According to another preferred embodiment of three-phase bridge-type rectifier of the present invention, intermediate circuit wherein comprises three polarity free capacitors between the intermediate node that is connected to three-phase reactor and dc bus series capacitance.Replacedly, this circuit also comprises an inductance element between the intermediate node that is connected three electric capacity and dc bus series capacitance.
According to another preferred embodiment of three-phase bridge-type rectifier of the present invention, also comprise the dc bus filter inductance that is connected the three-phase bridge rectifier group.
Three-phase bridge-type rectifier according to the present invention, can suppress harmonic content and make it satisfy IEC EN6100-3-2 standard during less than 16A at the incoming line electric current.And during greater than 16A, can make harmonic content THD≤15% according to three-phase bridge-type rectifier of the present invention at the incoming line electric current; For above-mentioned two kinds of situations, when 25% nominal load is above, according to power factor 〉=85% of three-phase bridge-type rectifier of the present invention; Under the situation more than 60% nominal load, can reach more than 95% according to the power factor of three-phase bridge-type rectifier of the present invention.Therefore, can suppress and protect interfering with each other or influence and reduced capacity requirement between electrical network and this device or the system effectively according to three-phase bridge-type rectifier of the present invention to the dc bus filter capacitor.
Brief description of drawings:
Fig. 1 is the circuit diagram of the three-phase bridge-type rectifier of prior art;
Fig. 2 is the circuit diagram according to first preferred embodiment of three bridge bridge-type rectifiers of the present invention;
Fig. 3 is the circuit diagram according to second preferred embodiment of three bridge bridge-type rectifiers of the present invention;
Fig. 4 is according to the circuit diagram that is the 3rd preferred embodiment of three bridge bridge-type rectifiers of the present invention;
Fig. 5 is the circuit diagram according to the 4th preferred embodiment of three bridge bridge-type rectifiers of the present invention;
Fig. 6 is the circuit diagram according to the 5th preferred embodiment of three bridge bridge-type rectifiers of the present invention;
Below, in conjunction with the accompanying drawings to a preferred embodiment of the present invention will be described in detail.
As shown in Figure 2, comprise a three-phase reactor T, by the rectifier diode group D of serial connection according to the three-phase bridge-type rectifier of the first embodiment of the present invention 1With D 4, D 2With D 5, and D 3With D 6The three-phase bridge rectifier circuit that forms is by capacitor C 1, C 2, C 3The cooperation reactor that forms carries out power factor correction and harmonic wave suppresses circuit, and dc bus electrochemical capacitor C 4And C 5
From the 380V of electrical network, the input of the three-phase of 50HZ AC power u, v, w are connected with three-phase reactor T respectively.Three-phase output end A, the B of three-phase reactor T, C respectively with the rectifier diode D that is connected in series 1With D 4, D 2With D 5, and D 3With D 6Between node connect.Rectifier diode D 1, D 2, D 3Common cathode end node and dc-link capacitance C 4P end connect and rectifier diode D 4, D 5, D 6The public anode end node then with dc-link capacitance C 5N end connect.And, three-phase output end A, the B of this three-phase reactor T, C respectively with capacitor C 1, C 2, C 3An end connect and this capacitor C 1, C 2, C 3The other end then be connected to each other in node D.This node D again with the dc bus electrochemical capacitor C that is connected in series 4And C 5Between node M connect, thereby form line DM.At last, export to the DC load circuit supply by port P and N.
Compare from Fig. 1 of Fig. 2 and prior art, can clearly be seen that, in the three-phase bridge-type rectifier of prior art, removed dc bus filter inductance L according to the first embodiment of the present invention 1, and inserted three-phase reactor T at three-phase power input end, and at this three-phase reactor T and dc bus electrochemical capacitor C 4And C 5Intermediate node between inserted three capacitor C respectively 1, C 2, C 3, and formed line DM.
The benefit that three-phase reactor T is connected three-phase power input end is that this three-phase reactor T at first can be respectively carry out filtering to the three-phase alternating-current supply of input, below with reference to the course of work of Fig. 2 explanation according to three-phase bridge-type rectifier of the present invention.The u of three-phase alternating-current supply with input is example mutually, being between positive half period of the input voltage of u phase, u phase power source voltage greater than zero but the A point voltage less than the P point voltage, rectifier diode D then 1The back-pressure of itself is setovered and not conducting.But because u phase input voltage can pass through the winding of three-phase reactor simultaneously to capacitor C 1Charge, just formed input current, guaranteed the continuity of input current, with the rising of u phase input voltage, rectifier diode D 1Thereby become the malleation biasing and conducting, the generation input current; Rise to maximum and drop to during zero at u phase input voltage, since the effect of the afterflow of the inductance of reactor T, capacitor C 1Be transfused to the symmetry of voltage charging and three-phase circuit work, can guarantee the continuous of electric current, electric current does not have the interruption phenomenon, and near changing with sinusoidal rule.
Because the symmetry of three-phase circuit work, the v of input three phase mains reaches mutually with w mutually and adds to rectifier diode D 2, D 3, D 4, D 5, and D 6The course of work also similar with it.Like this, as long as circuit parameter is coordinated with supporting mutually with load, just can almost be sinusoidal three-phase input current, improve power factor effectively and suppress harmonic wave.According to three capacitor C that embodiments of the invention increased 1, C 2, C 3Rectification input charging and energy storage effect are provided, and the effect by three-phase reactor T, improved power factor on the one hand, suppressed harmonic wave effectively, make simultaneously shown in 2 kinds in accompanying drawing that the line voltage waveform approaches two-way rectangular pulse waveform between A, B, the C, thereby reduced capacity requirement the dc bus electrochemical capacitor.
Like this, as long as at physical circuit Capacity design three-phase reactor T and capacitor C 1, C 2, C 3, C 4, and C 5Parameter, just can make harmonic content THD less than 15%, power factor also can reach more than 95% when nominal load, thereby realizes the effect that the present invention proposes.Particularly, in the circuit of the first embodiment according to the invention shown in the accompanying drawing 2, the reactance value of this three-phase reactor T is 18 milihenries, capacitor C 1, C 2, and C 3Capacitance be 20 microfarads, dc bus electrochemical capacitor C 4And C 5Capacitance be 470 microfarads, the rectifier diode D of bridge rectifier 1, D 2, D 3, D 4, D 5, and D 6Select three-phase commutation bridge heap IXYS.VU082-16NO7 for use, the DC load rated capacity is 6 kilowatts, has reached following effect: harmonic content reaches IEC EN61000-3-2 harmonic wave limit standard less than 12%; Power factor is up to 99.4%, is 3.6KW (60% rated capacity) when above at the DC load capacity, and power factor reaches more than 95%; At the DC load capacity is 1.5KW (25% rated capacity) when above, and power factor reaches more than 85%.
Fig. 3 is the circuit diagram of three-phase bridge-type rectifier according to a second embodiment of the present invention.As shown in Figure 3, identical with first embodiment, the 380V of electrical network, three-phase u, the v of 50HZ input ac power, w are connected with three-phase reactor T respectively.Three-phase output end A, the B of this three-phase reactor T, C respectively with the rectifier diode D that is connected in series that forms bridge rectifier 1With D 4, D 2With D 5, and D 3With D 6Between node connect.Diode D 1, D 2, and D 3Common cathode end node P and the dc bus electrochemical capacitor C that is connected in series 4An end connect and diode D 4, D 5, D 6Public anode end node N and capacitor C 5An end connect.And, three-phase output end A, the B of this three-phase reactor T, C respectively with capacitor C 1, C 2, C 3An end connect and capacitor C 1, C 2, C 3The public node D that is connected in of the other end.Different with first embodiment shown in Figure 2 is to be provided with and dc bus electrochemical capacitor C between this P point and N point according to a second embodiment of the present invention 4And C 5Two resistance R that are connected in series in parallel 1And R 2This resistance R 1And R 2Between node L and this capacitor C 1, C 2, and C 3Node D be connected, thereby form line DL.At last, power to load circuit by node P and N output.
According to second embodiment of the present invention and first embodiment comparison shown in Figure 2, increased resistance R 1And R 2, its purpose is to control dc bus electrochemical capacitor C 4And C 5The fluctuation range with load of output dc voltage, make that DC bus-bar voltage changes in preset range, and still can reach purpose and the effect that improves power factor and suppress input harmonics simultaneously, preferably, according to the second embodiment of the invention resistance R 1And R 2Be 50 kilo-ohms, other parameter is identical with embodiment.
The circuit structure of the three-phase bridge-type rectifier of the 3rd embodiment of the present invention as shown in Figure 4, in the figure, all and circuit components identical Fig. 2 are all represented with same numeral.Can clearly be seen that from Fig. 4, remove and change three-phase reactor T wherein into three single-phase reactance L a, L b, L cIn addition (inductance value can keep inconvenience), other parts are fully identical with the circuit structure of Fig. 2.Can reach the effect of Fig. 2 of the present invention equally, be that structural compactness, volume and weight are poor slightly.
According to the circuit structure of the three-phase bridge-type rectifier of the 4th embodiment of the present invention as shown in Figure 5, in the figure, allly all represent with same numeral with circuit components identical Fig. 2.Can clearly be seen that from Fig. 5, remove and between node D and M, inserted an inductance component L nSo that beyond the restriction injection current, other parts are fully identical with the circuit structure of Fig. 2.Between node D and M, insert this inductance component L at 2 nBenefit be suitably to limit input current, preferably, the inductance component L in the three-phase bridge-type rectifier of a fourth embodiment in accordance with the invention nReactance value is 1.5 milihenries.
In addition, can certainly be as the 3rd embodiment, change wherein three-phase reactor T into three single-phase reactance L a, L b, and L c
According to the circuit structure of the three-phase bridge-type rectifier of the 5th embodiment of the present invention as shown in Figure 6.In the figure, components identical is all represented with same numeral in the circuit of all and Fig. 3.Can clearly be seen that from Fig. 6, remove in resistance R 1And R 2The last capacitor C of two serial connections in parallel 6And C 7In addition, fully identical with the circuit structure of Fig. 3.In resistance R 1And R 2The capacitor C of last two serial connections in parallel 6And C 7For under certain loading condition, can suitably adjusting DC bus-bar voltage, preferably, the capacitor C of two serial connections 6And C 7Capacitance be 20 microfarads.
Through theoretical research and simulation calculation, and obtain experiment confirm, adopt three-phase bridge-type rectifier of the present invention to have following effect:
1. under the situation of incoming line electric current, can make harmonic content reach the IECEN6100-3-2 standard less than 16A; And under the situation of incoming line electric current, can suppress harmonic content THD≤15% greater than 16A;
2. under the situation more than 25% nominal load, power factor (PF) 〉=85%; Under the situation more than 60% nominal load, power factor reaches more than 95%;
3. can suppress that the high-frequency electromagnetic to electrical network disturbs (EMI) or harmonic pollution between device of the present invention inner or device of the present invention and the system, simultaneously again can be to protecting effectively from interference such as the harmonic wave of electrical network or distortion and suppressing; And
4. reduced capacity requirement to the dc bus filter capacitor.
With reference to each accompanying drawing, describe most preferred embodiment of the present invention in detail above, still, should not think that the present invention only only limits to each above-mentioned embodiment.Those skilled in the art, inspiration by the various embodiments described above, be not difficult three-phase bridge-type rectifier according to the present invention is made various improvement, change or replacement, therefore, these improvement, change or replacement should not thought to have broken away from design of the present invention or claims institute restricted portion.

Claims (8)

1. three-phase bridge-type rectifier comprises:
Three-phase bridge rectifier group, described three-phase bridge rectifier group comprise pair of output and three inputs;
First dc-link capacitance that is connected in series and second dc-link capacitance, between first dc-link capacitance of described series connection and second dc-link capacitance intermediate node is arranged, first dc-link capacitance of described series connection and second dc-link capacitance are connected on the pair of output of this three-phase bridge rectifier group;
Described three phase rectifier device is characterised in that also and comprises:
Be used for three-phase input power supply is carried out Filtering Processing and cooperates with subsequent conditioning circuit and can improve the reactive components of power factor, described reactive components is connected to three-phase and imports between three inputs of power supply and described three-phase bridge rectifier group; And
Be used to cooperate reactive components to carry out the intermediate circuit of mainly forming of power factor correction and inhibition harmonic wave by three polarity free capacitors, described intermediate circuit has three ends and is connected with three inputs of described three-phase bridge rectifier group respectively, and the other end is connected the intermediate node place of described first dc-link capacitance that is connected in series and second dc-link capacitance.
2. three-phase bridge-type rectifier according to claim 1, wherein said reactive components are three-phase reactors.
3. three-phase bridge-type rectifier according to claim 1, wherein said reactive components are the single-phase reactors of three separation.
4. three-phase bridge-type rectifier according to claim 2, wherein said intermediate circuit comprise three polarity free capacitors that separate between the intermediate node of end that the input that is connected to described three-phase reactor and rectifier group links to each other and described dc bus series capacitance.
5. three-phase bridge-type rectifier according to claim 3, wherein said intermediate circuit also comprise an inductance element between the intermediate node that is connected described three electric capacity and described dc bus series capacitance.
6. three-phase bridge-type rectifier according to claim 3, also comprise the induction reactance parts that are used for dc bus filtering, described induction reactance parts one end links to each other with any one output of described three-phase bridge rectifier group, and the other end is connected dc-link capacitance with this output node links to each other.
7. three-phase bridge-type rectifier comprises:
Three-phase bridge rectifier group, described three-phase bridge rectifier group comprise pair of output and three inputs;
First dc-link capacitance that is connected in series and second dc-link capacitance, first dc-link capacitance of described series connection and second dc-link capacitance are connected on the pair of output of this three-phase bridge rectifier group;
Described three phase rectifier device is characterised in that also and comprises:
Be used for three-phase input power supply is carried out Filtering Processing and cooperates with subsequent conditioning circuit and can improve the reactive components of power factor, described reactive components is connected to three-phase and imports between three inputs of power supply and described three-phase bridge rectifier group; And
Be used to cooperate reactive components to carry out power factor correction and suppress the intermediate circuit that mainly comprises three polarity free capacitors and first resistance (R1), second resistance (R2) of harmonic wave, an end of three polarity free capacitors is connected with three inputs of described three-phase bridge rectifier group respectively in the described intermediate circuit, between first resistance (R1) of described polyphone and second resistance (R2) intermediate node is arranged.This intermediate node links to each other with the other end of three polarity free capacitors.First resistance (R1) and second resistance (R2) of described polyphone are connected in parallel on the pair of output of three-phase bridge-type rectifier.
8. three-phase bridge-type rectifier according to claim 7, wherein said intermediate circuit also wraps two series capacitances, described two polyphone electric capacity are connected in parallel on the pair of output of three-phase bridge-type rectifier, the intermediate node of the intermediate node of described two series capacitances and above-mentioned series connection first resistance (R1), second resistance (R2) interconnects, thereby the intermediate node of a connection is provided.
CN 99106059 1999-04-29 1999-04-29 Three-phase bridge-type rectifier Expired - Fee Related CN1115765C (en)

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* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN103296913B (en) * 2012-03-02 2016-06-22 台达电子企业管理(上海)有限公司 Inverter and active power filter system
CN103812366B (en) * 2012-11-08 2017-07-28 上海儒竞电子科技有限公司 Three-phase controlled rectifier circuit
CN106058895A (en) * 2016-08-04 2016-10-26 三河市汇莹电气设备制造有限公司 Reactive power compensator
CN110336458B (en) * 2019-05-10 2020-05-26 珠海格力电器股份有限公司 Harmonic suppression circuit, power supply with same and air conditioner
CN112350556B (en) * 2020-11-16 2024-07-19 上海华电奉贤热电有限公司 Harmonic suppression circuit of frequency converter

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