CN102075101A - Single-phase full-control rectifier current-limiting device and work method thereof - Google Patents

Single-phase full-control rectifier current-limiting device and work method thereof Download PDF

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Publication number
CN102075101A
CN102075101A CN 201110020309 CN201110020309A CN102075101A CN 102075101 A CN102075101 A CN 102075101A CN 201110020309 CN201110020309 CN 201110020309 CN 201110020309 A CN201110020309 A CN 201110020309A CN 102075101 A CN102075101 A CN 102075101A
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igbt
phase full
controlled rectifier
current
rectifier bridge
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CN 201110020309
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CN102075101B (en
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虞坚阳
杨振宇
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江苏省电力公司常州供电公司
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Abstract

The invention relates to a single-phase full-control rectifier current-limiting device capable of preventing the damage to the device in a moment of switching on a single-phase full-control rectifier bridge with an alternating current bus and a work method thereof. The device comprises the single-phase full-control rectifier bridge, a direct current filter capacitor, a single-phase bridge type inverter and a CPU (Central Processing Unit); and a soft charging circuit is connected with the alternating current input end of the single-phase full-control rectifier bridge in series. For solving the problem that the great over-current is out of control when the uncontrollable rectifier unlocking is switched to the controllable rectifier stage in the process of the single-phase full-control rectifier, the single-phase full-control rectifier current-limiting strategy is applied to the invention, so that not only can the single-phase charging current be effectively limited, but also the capacitor can be stably charged and the oscillation process of the capacitor can be prevented.

Description

Single-phase full-controlled rectifier current-limiting apparatus and method of work thereof

Technical field

The present invention relates to the technical field of single-phase full-controlled rectifier, specifically is a kind of single-phase full-controlled rectifier current-limiting apparatus and rectification current-limiting method thereof.

Background technology

Fig. 1 is single-phase bridge current transformer back-to-back, and its main part is made up of single-phase bridge rectifier (that is: single-phase full-controlled rectifier bridge A), dc filter capacitor C, single-phase bridge type inverter B, comprises auxiliary bodies such as fuse F in addition.Single-phase bridge rectifier is by IGBT module (T 1~T 4) constitute.

Close a floodgate moment at single-phase full-controlled rectifier bridge A and ac bus, on the one hand, because the voltage of dc filter capacitor C can not suddenly change, and initial voltage is 0, on the other hand, because the direct voltage u at dc filter capacitor C two ends DcDo not set up as yet, so IGBT module (T 1~T 4) uncontrollable.For these reasons, at the beginning of powering on, alternating current is by described IGBT module (T 1~T 4) in fly-wheel diode do not control rectification because the impedance of whole flow cycle is less, and pressure reduction is very big, easily forms bigger short-circuit impact electric current, is equivalent to the short circuit with single-phase full-controlled rectifier bridge A this moment.Because the cost problem can not determined the power cell component parts by this temporary impact electric current.But, must cause device failure again if do not handle.

In addition, make single-phase full-controlled rectifier bridge A be operated in the controlled rectification stage, described direct voltage u DcStill need the lifting of charging, need carry out release this moment with the IGBT module, to carry out the High Power Factor rectification, continues dc filter capacitor C is charged and voltage stabilizing.Problem appears at the moment of release charging, and the alternating current amplitude of the single-phase full-controlled rectifier bridge A that flows through increases tens of times suddenly, and direct voltage u DcAlso occur overcharging and the vibrational stabilization process, as shown in Figure 2.Alternating current has this moment constituted serious threat to described IGBT module.Therefore, in single-phase full-control type switching process, never control the rectification release and switch to controlled rectification during the stage, overcurrent situation out of control significantly can occur, power device has been constituted serious threat.The analysis of causes: the soft charging circuit of IGBT release moment, two thyristor Tr conductings of soft charging link, its influence can be ignored.Suppose that the voltage on AC side live wire this moment is the highest, because two IGBT(T of same brachium pontis 1And T 2, T 3And T 4) logic of turn-on and turn-off reciprocal (dc-side short-circuit that causes when preventing two IGBT of same brachium pontis conducting simultaneously), so the hypothesis IGBT module T on the live wire brachium pontis at this moment 2End, then IGBT module T 1By the fly-wheel diode conducting, as Fig. 3, if zero line brachium pontis two tubulose attitudes are by IGBT module T 4Conducting switches to IGBT module T 3Conducting AC side then will occur by IGBT module T 1And T 3The phenomenon that is short-circuited; If the IGBT module T in the live wire brachium pontis 2Conducting is as IGBT module T 4Cut when logical by disconnected, can occur the electric current phenomenon that heightens equally.

How to solve the problems of the technologies described above, be the technical barrier of this area.

Summary of the invention

The technical problem to be solved in the present invention provides a kind of preventing and causes the single-phase full-controlled rectifier current-limiting apparatus of device failure in single-phase full-controlled rectifier bridge and ac bus moment of closing a floodgate, and provide a kind of and be suitable in single-phase full-control type switching process, never control the rectification release and switch to controlled rectification during the stage, prevent overcurrent rectification current-limiting method out of control significantly.

For solving the technical problem that causes device failure in single-phase full-controlled rectifier bridge and ac bus combined floodgate moment, the invention provides a kind of single-phase full-controlled rectifier current-limiting apparatus, it comprises: single-phase full-controlled rectifier bridge A, dc filter capacitor C, single-phase bridge type inverter B and CPU element; The dc output end of single-phase full-controlled rectifier bridge A links to each other with the dc supply input of the two ends of dc filter capacitor C and single-phase bridge type inverter B; CPU element links to each other with the rectification control end of single-phase full-controlled rectifier bridge A and the inversion control end of single-phase bridge type inverter B; The ac input end of described single-phase full-controlled rectifier bridge A is provided with the current transformer that links to each other with described CPU element, is provided with the voltage sensor that links to each other with described CPU element between the positive and negative electrode of dc filter capacitor C; It is characterized in that: the ac input end at single-phase full-controlled rectifier bridge A is connected in series a soft charging circuit D; This soft charging circuit D comprises: thyristor Tr, the current-limiting resistance R in parallel with this thyristor Tr, the gate pole of thyristor Tr links to each other with described CPU element.

Described single-phase full-controlled rectifier bridge A comprises two groups of IGBT unit, each is organized the IGBT unit and comprises: upper and lower IGBT module, each IGBT module comprises: IGBT and fly-wheel diode, the anode of this fly-wheel diode connects the emitter of IGBT, the negative electrode of fly-wheel diode connects the collector electrode of IGBT, and the grid of each IGBT is the rectification control end of described single-phase full-controlled rectifier bridge A; The emitter of IGBT in the last IGBT module connects down the collector electrode of the IGBT in the IGBT module; The collector electrode of IGBT on each in the IGBT module connects the positive pole of described dc filter capacitor C, and the emitter of the IGBT in each time IGBT module connects the negative pole of described dc filter capacitor C; The contact of the upper and lower IGBT module in two groups of IGBT unit respectively with AC power in live wire link to each other with zero line.

For solving in single-phase full-control type switching process, never controlling the rectification release switches to controlled rectification and occurs overcurrent technical problem out of control significantly during the stage, the invention provides the method for work of single-phase full-controlled rectifier current-limiting apparatus, it comprises: when CPU element records the ac input end connection AC power of described single-phase full-controlled rectifier bridge A by described current transformer, the IGBT that CPU element is controlled in described thyristor Tr and each IGBT module ends, and single-phase full-controlled rectifier bridge A is in does not control rectification state; The fly-wheel diode of each the IGBT module of AC power in described current-limiting resistance R and single-phase full-controlled rectifier bridge A carries out precharge to dc filter capacitor C; Record the direct voltage u at dc filter capacitor C two ends by described voltage sensor when CPU element DcAfter stable, CPU element triggers described thyristor Tr conducting, with the described current-limiting resistance R of bypass.

Further, when CPU element began to control single-phase full-controlled rectifier bridge A and works in the controlled rectification state, CPU element detected the transient current of the ac input end of single-phase full-controlled rectifier bridge A by described current transformer; Absolute value I when described transient current〉I LimAnd the direction of this transient current is to flow into single-phase full-controlled rectifier bridge A, then CPU element is controlled the IGBT conducting and ending respectively in the upper and lower IGBT module in the described left IGBT unit, and the IGBT that controls the upper and lower IGBT module in the described right IGBT unit respectively by and conducting; Absolute value I when described transient current〉I LimAnd the direction of this transient current is to flow out single-phase full-controlled rectifier bridge A, then CPU element control in the upper and lower IGBT module in the described left IGBT unit IGBT respectively by and conducting, and the IGBT that controls the upper and lower IGBT module in described right IGBT unit conducting and ending respectively; Described I LimBe the protection limit value of the IGBT module among the described single-phase full-controlled rectifier bridge A, this protection limit value is the product parameters of IGBT module, can draw by relevant detection or test.

The present invention has positive effect: when (1) single-phase full-controlled rectifier current-limiting apparatus of the present invention is worked, when CPU element records the ac input end connection AC power of single-phase full-controlled rectifier bridge A by described current transformer, the IGTB that CPU element is controlled in each thyristor Tr and each IGBT module ends, and single-phase full-controlled rectifier bridge A is in does not control rectification state; AC power fly-wheel diode in each IGBT module in described current-limiting resistance R and single-phase full-controlled rectifier bridge A carries out precharge to dc filter capacitor C; Because the existence of current-limiting resistance R has limited overshoot current; Record the direct voltage u at dc filter capacitor C two ends by described voltage sensor when CPU element DcAfter stable, CPU element triggers thyristor Tr conducting, with the described current-limiting resistance R of bypass.This moment is because described direct voltage u DcHave certain initial voltage, the pressure reduction of single-phase full-controlled rectifier bridge A both sides is less, thereby makes the charging current of dc filter capacitor C less relatively, so be suitable for avoiding causing device failure in single-phase full-controlled rectifier bridge and ac bus moment of closing a floodgate.(2) for solving in single-phase full-control type switching process, never controlling the rectification release switches to controlled rectification and occurs overcurrent technical problem out of control significantly during the stage, the present invention has adopted single-phase full-controlled rectifier current limliting strategy, this strategy not only can limit single-phase charging current effectively, and can steadily charge to capacitor, prevent its oscillatory process.

Description of drawings

For the easier quilt of content of the present invention is clearly understood, below the specific embodiment and in conjunction with the accompanying drawings of basis, the present invention is further detailed explanation, wherein

Fig. 1 is the single-phase back-to-back fully controlled bridge converter topologies schematic diagram among the embodiment.

Fig. 2 is the switching process of the single-phase full-controlled rectifier bridge when adopting soft charging circuit to carry out soft charging, and wherein, wave band 1 is not controlled commutation phase for the band current-limiting resistance; Wave band 2 is not controlled commutation phase during for the thyristor conducting in the soft charging circuit; Wave band 3 is the controlled rectification stage.

Fig. 3 is single-phase full-controlled rectifier bridge brachium pontis short circuit overcurrent schematic diagram.

Embodiment

See Fig. 1, the single-phase full-controlled rectifier current-limiting apparatus of present embodiment comprises: single-phase full-controlled rectifier bridge A, dc filter capacitor C, single-phase bridge type inverter B and CPU element; The dc output end of single-phase full-controlled rectifier bridge A links to each other with the dc supply input of the two ends of dc filter capacitor C and single-phase bridge type inverter B; CPU element links to each other with the rectification control end of single-phase full-controlled rectifier bridge A and the inversion control end of single-phase bridge type inverter B; The ac input end of described single-phase full-controlled rectifier bridge A is provided with the current transformer that links to each other with described CPU element, is provided with the voltage sensor that links to each other with described CPU element between the positive and negative electrode of dc filter capacitor C; It is characterized in that: the ac input end at single-phase full-controlled rectifier bridge A is connected in series a soft charging circuit D; This soft charging circuit D comprises: thyristor Tr, the current-limiting resistance R in parallel with this thyristor Tr, the gate pole of thyristor Tr links to each other with described CPU element.CPU element comprises that a slice DSP, ARM or single-chip microcomputer etc. can only control chips at least.Described thyristor Tr adopts the one-way SCR of a pair of reversal connection, also can adopt single bidirectional triode thyristor.

Described single-phase full-controlled rectifier bridge A comprises two groups of IGBT unit, each is organized the IGBT unit and comprises: upper and lower IGBT module, each IGBT module comprises: IGBT and fly-wheel diode, the anode of this fly-wheel diode connects the emitter of IGBT, the negative electrode of fly-wheel diode connects the collector electrode of IGBT, and the grid of each IGBT is the rectification control end of described single-phase full-controlled rectifier bridge A; The emitter of IGBT in the last IGBT module connects down the collector electrode of the IGBT in the IGBT module; The collector electrode of IGBT on each in the IGBT module connects the positive pole of described dc filter capacitor C, and the emitter of the IGBT in each time IGBT module connects the negative pole of described dc filter capacitor C; The contact of the upper and lower IGBT module in two groups of IGBT unit respectively with AC power in live wire link to each other with zero line.

The method of work of the single-phase full-controlled rectifier current-limiting apparatus of present embodiment, it comprises: when CPU element records the ac input end connection AC power of described single-phase full-controlled rectifier bridge A by described current transformer, the IGBT that CPU element is controlled in described thyristor Tr and each IGBT module ends, and single-phase full-controlled rectifier bridge A is in does not control rectification state; The fly-wheel diode of each the IGBT module of AC power in described current-limiting resistance R and single-phase full-controlled rectifier bridge A carries out precharge to dc filter capacitor C; Record the direct voltage u at dc filter capacitor C two ends by described voltage sensor when CPU element DcAfter stable, CPU element triggers described thyristor Tr conducting, with the described current-limiting resistance R of bypass.

When CPU element began to control single-phase full-controlled rectifier bridge A and works in the controlled rectification state, CPU element detected the transient current of the ac input end of single-phase full-controlled rectifier bridge A by described current transformer; Absolute value I when described transient current〉I LimAnd the direction of this transient current is to flow into single-phase full-controlled rectifier bridge A, then CPU element is controlled the IGBT conducting and ending respectively in the upper and lower IGBT module in the described left IGBT unit, and the IGBT that controls the upper and lower IGBT module in the described right IGBT unit respectively by and conducting; Absolute value I when described transient current〉I LimAnd the direction of this transient current is to flow out single-phase full-controlled rectifier bridge A, then CPU element control in the upper and lower IGBT module in the described left IGBT unit IGBT respectively by and conducting, and the IGBT that controls the upper and lower IGBT module in described right IGBT unit conducting and ending respectively; Described I LimProtection limit value for the IGBT module among the described single-phase full-controlled rectifier bridge A.

The foregoing description only is for example of the present invention clearly is described, and is not to be qualification to embodiments of the present invention.For those of ordinary skill in the field, can also make other changes in different forms on the basis of the above description.Here need not also can't give exhaustive to all execution modes.And these belong to conspicuous variation or the change that spirit of the present invention extended out and still are among protection scope of the present invention.

Claims (4)

1. a single-phase full-controlled rectifier current-limiting apparatus comprises: single-phase full-controlled rectifier bridge (A), dc filter capacitor (C), single-phase bridge type inverter (B) and CPU element;
The dc output end of single-phase full-controlled rectifier bridge (A) links to each other with the two ends of dc filter capacitor (C) and the dc supply input of single-phase bridge type inverter (B); CPU element links to each other with the rectification control end of single-phase full-controlled rectifier bridge (A) and the inversion control end of single-phase bridge type inverter (B); The ac input end of described single-phase full-controlled rectifier bridge (A) is provided with the current transformer that links to each other with described CPU element, is provided with the voltage sensor that links to each other with described CPU element between the positive and negative electrode of dc filter capacitor (C); It is characterized in that:
Ac input end at single-phase full-controlled rectifier bridge (A) is connected in series a soft charging circuit (D); This soft charging circuit (D) comprising: thyristor (Tr), the current-limiting resistance (R) in parallel with this thyristor (Tr), the gate pole of thyristor (Tr) links to each other with described CPU element.
2. single-phase full-controlled rectifier current-limiting apparatus according to claim 1, it is characterized in that: described single-phase full-controlled rectifier bridge (A) comprises left and right IGBT unit, each IGBT unit comprises: upper and lower IGBT module, each IGBT module comprises: IGBT and fly-wheel diode, the anode of this fly-wheel diode connects the emitter of IGBT, the negative electrode of fly-wheel diode connects the collector electrode of IGBT, and the grid of each IGBT is the rectification control end of described single-phase full-controlled rectifier bridge (A); The emitter of IGBT in the last IGBT module connects down the collector electrode of the IGBT in the IGBT module; The collector electrode of IGBT on each in the IGBT module connects the positive pole of described dc filter capacitor (C), and the emitter of the IGBT in each time IGBT module connects the negative pole of described dc filter capacitor (C); The contact of the upper and lower IGBT module in the contact of the upper and lower IGBT module in the IGBT unit, a left side and the right IGBT unit respectively with AC power in live wire link to each other with zero line.
3. the method for work of single-phase full-controlled rectifier current-limiting apparatus according to claim 2, it is characterized in that: when CPU element records the ac input end connection AC power of described single-phase full-controlled rectifier bridge (A) by described current transformer, the IGBT that CPU element is controlled in described thyristor (Tr) and each the IGBT module ends, and single-phase full-controlled rectifier bridge (A) is in does not control rectification state; The fly-wheel diode of each the IGBT module of AC power in described current-limiting resistance (R) and single-phase full-controlled rectifier bridge (A) carries out precharge to dc filter capacitor (C); Record the direct voltage (u at dc filter capacitor (C) two ends by described voltage sensor when CPU element Dc) stable after, CPU element triggers described thyristor (Tr) conducting, with the described current-limiting resistance of bypass (R).
4. according to the method for work of claim 2 or 3 described single-phase full-controlled rectifier current-limiting apparatus, it is characterized in that: when CPU element began to control single-phase full-controlled rectifier bridge (A) and works in the controlled rectification state, CPU element detected the transient current of the ac input end of single-phase full-controlled rectifier bridge (A) by described current transformer;
Absolute value I when described transient current〉I LimAnd the direction of this transient current is to flow into single-phase full-controlled rectifier bridge (A), then CPU element is controlled the IGBT conducting and ending respectively in the upper and lower IGBT module in the described left IGBT unit, and the IGBT that controls the upper and lower IGBT module in the described right IGBT unit respectively by and conducting;
Absolute value I when described transient current〉I LimAnd the direction of this transient current is to flow out single-phase full-controlled rectifier bridge (A), then CPU element control in the upper and lower IGBT module in the described left IGBT unit IGBT respectively by and conducting, and the IGBT that controls the upper and lower IGBT module in described right IGBT unit conducting and ending respectively;
Described I LimProtection limit value for the IGBT module in the described single-phase full-controlled rectifier bridge (A).
CN 201110020309 2011-01-18 2011-01-18 Single-phase full-control rectifier current-limiting device and work method thereof CN102075101B (en)

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Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN103916031A (en) * 2013-01-09 2014-07-09 中国长城计算机深圳股份有限公司 Half-controlled bridge rectifier with surge suppression function

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH04372582A (en) * 1991-06-19 1992-12-25 Fuji Electric Co Ltd Capacitor rush current preventing circuit for rectifier
US6038155A (en) * 1998-03-31 2000-03-14 International Rectifier Corporation Three phase SCR rectifier bridge with soft start control IC
CN201656760U (en) * 2010-03-22 2010-11-24 临沂施乃通电气技术有限公司 Surge-prevention soft starting circuit
CN201937480U (en) * 2011-01-18 2011-08-17 江苏省电力公司常州供电公司 Single-phase full-control rectifying and current-limiting device

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH04372582A (en) * 1991-06-19 1992-12-25 Fuji Electric Co Ltd Capacitor rush current preventing circuit for rectifier
US6038155A (en) * 1998-03-31 2000-03-14 International Rectifier Corporation Three phase SCR rectifier bridge with soft start control IC
CN201656760U (en) * 2010-03-22 2010-11-24 临沂施乃通电气技术有限公司 Surge-prevention soft starting circuit
CN201937480U (en) * 2011-01-18 2011-08-17 江苏省电力公司常州供电公司 Single-phase full-control rectifying and current-limiting device

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN103916031A (en) * 2013-01-09 2014-07-09 中国长城计算机深圳股份有限公司 Half-controlled bridge rectifier with surge suppression function

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