CN106655819B - Protector for short-circuit current rectifier of bidirectional converter - Google Patents

Protector for short-circuit current rectifier of bidirectional converter Download PDF

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Publication number
CN106655819B
CN106655819B CN201611116262.XA CN201611116262A CN106655819B CN 106655819 B CN106655819 B CN 106655819B CN 201611116262 A CN201611116262 A CN 201611116262A CN 106655819 B CN106655819 B CN 106655819B
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igbt
short
rectifying
devices
igbta1
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CN106655819A (en
Inventor
谭国俊
李�浩
李辉
杨波
郑旺
丁玉侠
张祖亚
耿程飞
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Jiangsu Guochuan Electric Co ltd
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China Mining Drives and Automation Co Ltd
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    • H—ELECTRICITY
    • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02M—APPARATUS FOR CONVERSION BETWEEN AC AND AC, BETWEEN AC AND DC, OR BETWEEN DC AND DC, AND FOR USE WITH MAINS OR SIMILAR POWER SUPPLY SYSTEMS; CONVERSION OF DC OR AC INPUT POWER INTO SURGE OUTPUT POWER; CONTROL OR REGULATION THEREOF
    • H02M7/00—Conversion of ac power input into dc power output; Conversion of dc power input into ac power output
    • H02M7/02—Conversion of ac power input into dc power output without possibility of reversal
    • H02M7/04—Conversion of ac power input into dc power output without possibility of reversal by static converters
    • H02M7/12—Conversion of ac power input into dc power output without possibility of reversal by static converters using discharge tubes with control electrode or semiconductor devices with control electrode
    • H02M7/125—Avoiding or suppressing excessive transient voltages or currents
    • H—ELECTRICITY
    • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02M—APPARATUS FOR CONVERSION BETWEEN AC AND AC, BETWEEN AC AND DC, OR BETWEEN DC AND DC, AND FOR USE WITH MAINS OR SIMILAR POWER SUPPLY SYSTEMS; CONVERSION OF DC OR AC INPUT POWER INTO SURGE OUTPUT POWER; CONTROL OR REGULATION THEREOF
    • H02M1/00—Details of apparatus for conversion
    • H02M1/32—Means for protecting converters other than automatic disconnection
    • H—ELECTRICITY
    • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02M—APPARATUS FOR CONVERSION BETWEEN AC AND AC, BETWEEN AC AND DC, OR BETWEEN DC AND DC, AND FOR USE WITH MAINS OR SIMILAR POWER SUPPLY SYSTEMS; CONVERSION OF DC OR AC INPUT POWER INTO SURGE OUTPUT POWER; CONTROL OR REGULATION THEREOF
    • H02M1/00—Details of apparatus for conversion
    • H02M1/32—Means for protecting converters other than automatic disconnection
    • H02M1/325—Means for protecting converters other than automatic disconnection with means for allowing continuous operation despite a fault, i.e. fault tolerant converters

Abstract

The invention relates to a protection device for a short-circuit current rectifier of a bidirectional converter, which is characterized by comprising a set of rectifier devices, a power device IGBT, a clamping diode and a support capacitor, wherein the rectifier devices are connected with the power device IGBT in parallel to form two groups of uncontrolled rectifier bridge arms, and the support capacitor is connected with the power device IGBT in parallel. According to the technical scheme, the short-circuit current can be effectively ensured to flow through the rectifier device, so that the current flowing through the IGBT freewheeling diode is reduced within a bearable range, and the IGBT is effectively protected from being damaged.

Description

Protector for short-circuit current rectifier of bidirectional converter
Technical Field
The invention relates to a protection device, in particular to a protection device for a short-circuit current rectifying device of a bidirectional converter, and belongs to the technical field of rail transit power supply devices.
Background
In a rail transit system, traction power supply is used as a core and a power source, and the whole system is in an extremely critical position. At present, a traction power supply system of urban rail transit still generally adopts a mode of supplying power by a diode rectifier unit, and the power supply mode has the following defects: 1. the output direct-current voltage has large fluctuation; 2. inability to handle regenerative braking energy: 3. the system power factor is not controllable; the high-power traction power supply bidirectional converter composed of the fully-controlled power electronic device IGBT can thoroughly solve the defects of the diode rectifier unit.
Due to the application specificity of the rail traction power supply device, the fault of direct current side short circuit inevitably occurs in the using process. When a direct current side short circuit occurs, the IGBT is inevitably in a blocking state through internal protection, and at the moment, short-circuit current flows through the anti-parallel freewheeling diode in the module. Short-circuiting hair on DC sideIn order to ensure the detection function of the direct current switch on a direct current fault point in life, the bidirectional converter needs to be required not to immediately send a tripping instruction on an input/output side for protecting a power device of the bidirectional converter after blocking a pulse, namely the power device needs to meet the long-term tolerance requirement of short-circuit current. The freewheeling diode I of the IGBT is different from the mechanism of the rectifying device2the t parameter can not meet the requirement of short-circuit current tolerance far away, and if no measure is taken, the IGBT of the power device is damaged or even damaged due to the heat effect. Because the rail traction power supply device inevitably has short-circuit faults, although the bidirectional converter can solve the defects of the diode rectifier, if the tolerance problem of a power device in short circuit cannot be solved, the bidirectional converter cannot be popularized in industrial application. To address this problem, those skilled in the art have tried new solutions, but the problem has not been properly solved.
Disclosure of Invention
The invention provides a protection device for a short-circuit current rectifier of a bidirectional converter aiming at the technical problems in the prior art, and the technical scheme provides a power unit of the bidirectional converter for completing the functions of direct-current voltage-stabilizing output, braking energy feedback and system reactive compensation; the technical scheme provides a tolerance device for short-circuit current in direct-current short-circuit time division of a power unit of a bidirectional converter, which is used for protecting an IGBT (insulated gate bipolar translator), and secondly, the tolerance device can bear the short-circuit current without damage, ensures reliable installation in the power unit and does not need to increase the volume of the power unit.
In order to achieve the purpose, the technical scheme of the invention is that the protection device for the short-circuit current rectifier device of the bidirectional converter is characterized by comprising a set of rectifier device, a power device IGBT, a clamping diode and a support capacitor, wherein the rectifier device is connected with the power device IGBT in parallel to form two sets of short-circuit protection bridge arms; the rectifier is a silicon controlled rectifier; the rectifying devices comprise silicon controlled rectifier rectifying devices D1, D2, D3 and D4, the rectifying devices D1 and D2 are connected in series, D3 and D4 are connected in series, and the rectifying devices and the D3 and the D4 are respectively connected with IGBT bridge arms in parallel; the support capacitor comprises a support capacitor C13 and a support capacitor C14, and the support capacitor C13 and the support capacitor C14 are connected with the power device IGBT in parallel; the clamp diode comprises D11, D12, D21, D22; the power device IGBT comprises a 1# IGBTA1, a 1# IGBTA2, a 1# IGBTA3, a 1# IGBTA4, a 2# IGBTA1, a 2# IGBTA2, a 2# IGBTA3 and a 2# IGBTA4, wherein the 1# IGBTA2 and the 1# IGBTA3 are arranged between the 1# IGBTA1 and the 1# IGBTA4, and the 2# IGBTA2 and the 2# IGBTA3 are arranged between the 2# IGBTA1 and the 2# IGBTA 4; the clamping diodes D11 and D12 are connected in series and then connected in parallel at two ends of the power devices 1# IGBTA2 and 1# IGBTA3, the clamping diodes D21 and D22 are connected in series and then connected in parallel at two ends of the power devices 2# IGBTA2 and 2# IGBTA3, and the added rectifying devices have current flowing only after the IGBT blocking trigger pulse.
As an improvement of the present invention, the impedance value of the connection dc bus of the rectifying devices D1, D2, D3, D4 is less than 0.1m Ω.
As an improvement of the utility model, the internal resistance r of the rectifierT＝0.253mΩ。
As an improvement of the utility model, the mode of the direct crimping of 3mm copper bar is chooseed for use to rectifier device's connection, has guaranteed the reliability of crimping.
A protection device for a short-circuit current rectifying device of a bidirectional converter comprises the following working steps: step 1, when the bidirectional converter normally works, power devices IGBT, namely 1# IGBTA1-1# IGBTA4, 2# IGBTA1-2# IGBTA4, clamping diodes D11, D12, D21 and D22, and supporting capacitors C13 and C14 trigger the power devices to complete direct current voltage stabilization output, direct current energy feedback and system reactive compensation; step 2, protecting a locking pulse by IGBT (insulated gate bipolar translator), namely 1# IGBTA1-1# IGBTA4 and 2# IGBTA1-2# IGBTA4 when short-circuit fault occurs; step 3, short-circuit faults on the direct-current side are not removed, and short-circuit current is provided by the rectifying devices D1-D4 and the IGBT freewheeling diode in parallel; and 4, the internal resistance of the loop of the rectifying devices D1-D4 is far smaller than that of the IGBT freewheeling diode, most of short-circuit current flows through the loop of the rectifying devices D1-D4, and the IGBT freewheeling diode only bears small current.
Compared with the prior art, the invention has the advantages that 1) the technical scheme has ingenious overall design and compact structure; 2) the bidirectional converter short-circuit current rectifier protection device in the technical scheme enables the bidirectional converter to have the advantage of strong heavy current endurance capability of the diode rectifier, and also overcomes the defects that the output direct current voltage of the diode rectifier has large fluctuation, regenerative braking energy cannot be processed, and the system power factor is uncontrollable; 4) the technical scheme has low cost and is convenient for large-scale popularization and application.
Drawings
FIG. 1 is a schematic diagram of the electrical connections of the overall protective device;
FIG. 2 is a schematic diagram of the ON/OFF state of the present invention;
fig. 3 is a shunt actual measurement waveform diagram of a rectifying device, wherein a 2# channel is an alternating current incoming line current, and a 3# channel is a rectifying device current.
In the figure: a rectifying device: D1-D4, power device: 1# IGBTA1-1# IGBTA4, 2# IGBTA1-2# IGBTA4, clamp diode: d11, D12, D21 and D22, and a support capacitor: c13, C14.
The specific implementation mode is as follows:
for the purpose of enhancing an understanding of the present invention, the present embodiment will be described in detail below with reference to the accompanying drawings.
Example 1: referring to fig. 1, the protection device for the short-circuit current rectifying device of the bidirectional converter comprises a set of rectifying devices D1-D4, power devices IGBT (insulated gate bipolar translator) (1 # IGBTA1-1# IGBTA4, 2# IGBTA1-2# IGBTA4, clamp diodes D11, D12, D21, D22 and support capacitors C13 and C14, wherein the rectifying devices D1-D4 are connected with the power devices IGBT in parallel to form two groups of uncontrolled rectifying bridge arms, and the support capacitors are connected with the power devices IGBT in parallel; the rectifying device comprises rectifying devices D1, D2, D3 and D4, wherein the rectifying devices D1, D2, D3 and D4 are connected with the IGBT in parallel, one ends of the rectifying devices D1, D2, D3 and D4 are connected to a direct current bus, the other ends of the rectifying devices D1, D2, D3 and D4 are connected to an alternating current incoming line AC, the supporting capacitor comprises a supporting capacitor C13 and a supporting capacitor C14, and the supporting capacitor C13 and the supporting capacitor C14 are connected with the power device IGBT in parallel; the clamp diodes comprise D11, D12, D21 and D22, the power device IGBT comprises 1# IGBTA1, 1# IGBTA2, 1# IGBTA3, 1# IGBTA4, 2# IGBTA1, 2# IGBTA2, 2# IGBTA3 and 2# IGBTA4, wherein the 1# IGBTA2 and the 1# IGBTA3 are arranged between the 1# IGBTA1 and the 1# IGBTA4, and the 2# IGBTA2 and the 2# IGBTA3 are arranged between the 2# IGBTA1 and the 2# IGBTA 4; clamp diodes D11 and D12 are connected in series and then connected in parallel to both ends of power devices 1# IGBTA2 and 1# IGBTA3, and clamp diodes D21 and D22 are connected in series and then connected in parallel to both ends of power devices 2# IGBTA2 and 2# IGBTA 3. The technical scheme can effectively ensure that the short-circuit current flows through the rectifier device, so that the current flowing through the IGBT freewheeling diode is reduced in a bearable range, the IGBT is effectively protected from being damaged, the current flows through the installed rectifier device only after the IGBT blocks the trigger pulse, and the short-circuit fault cutting-off time is not allowed to exceed 1s, so that a heat dissipation device is not required to be additionally installed on the rectifier device, and the installation volume is reduced.
Example 2: referring to fig. 1, as the utility model discloses an improvement, rectifier device D1, D2, D3, D4's the impedance value of connecting the direct current generating line is less than 0.1m omega, can guarantee the heavy current tolerance when direct current side short circuit like this, and power device IGBT normally triggers during its normal operating condition for accomplish direct current steady voltage output, braking energy repayment, system reactive compensation, load current mainly triggers control regulation by the IGBT return circuit this moment.
Example 3: referring to fig. 1, fig. 2 is a schematic diagram of an operating schematic diagram of a short-circuit current tolerance protection device of a bidirectional converter, when a short-circuit fault occurs on a dc side, an IGBT blocks a trigger pulse due to a short protection response time of the IGBT, that is, the IGBT is in an open circuit state, and when a short-circuit current is still present, the short-circuit current is mainly provided by rectifying devices D1-D4, 1# IGBTA1-1# IGBTA4 and 2# IGBTA1-2# IGBTA4, and a freewheeling diode I of the IGBT due to a difference between the IGBT and the rectifying devices in mechanisms2the t parameter is small and cannot bear large current for a long time, so that short-circuit current is mainly provided by rectifying devices D1-D4 with small internal resistance. In order to ensure that the large current under the working condition is mainly provided by the rectifying devices D1-D4, the following measures are adopted: 1) the rectifier should satisfy I2t＝6125kA2s, internal resistance r of rectifierT0.253m omega, 2) rectifier deviceThe connection of selecting for use the mode of the direct crimping of 3mm copper bar, guaranteed the reliability of crimping.
The working principle is as follows: referring to fig. 1, 2 and 3, a protection device for a short-circuit current rectifying device of a bidirectional converter comprises the following working steps: step 1, when the bidirectional converter normally works, power devices IGBT, namely 1# IGBTA1-1# IGBTA4, 2# IGBTA1-2# IGBTA4, clamping diodes D11, D12, D21 and D22, and supporting capacitors C13 and C14 trigger the power devices to complete direct current voltage stabilization output, direct current energy feedback and system reactive compensation; step 2, protecting a locking pulse by IGBT (insulated gate bipolar translator), namely 1# IGBTA1-1# IGBTA4 and 2# IGBTA1-2# IGBTA4 when short-circuit fault occurs; step 3, short-circuit faults on the direct-current side are not removed, and short-circuit current is provided by the rectifying devices D1-D4 and the IGBT freewheeling diode in parallel; and 4, the internal resistance of the loop of the rectifying devices D1-D4 is far smaller than that of the IGBT freewheeling diode, most of short-circuit current flows through the loop of the rectifying devices D1-D4, and the IGBT freewheeling diode only bears small current. Fig. 3 is a measured waveform of a large current shunt during a short circuit, and it can be seen from the waveform that when a short circuit occurs, the ac incoming current detected by the 2# channel of the oscilloscope is 6.81kA, the current detected by the 3# channel of the oscilloscope is 6.63kA, and the current of the IGBT is only 6.81-6.63 ═ 0.18kA, that is, after the rectifying device is added, when a short circuit occurs, the current depends on the strong I of the rectifying device2the t heat capacity can effectively protect the IGBT from bearing the impact of large current, not only can protect the rectifier device from being damaged, but also can ensure that the IGBT can not be damaged.
The invention can also combine the technical characteristics described in example 2 with example 1 to form a new implementation.
It should be noted that the above-mentioned embodiments are not intended to limit the scope of the present invention, and all equivalent modifications and substitutions based on the above-mentioned technical solutions are within the scope of the present invention as defined in the claims.

Claims (5)

1. A protection device for a short-circuit current rectifier device of a bidirectional converter is characterized by comprising a set of rectifier device, a power device IGBT, a clamping diode and a support capacitor, wherein the rectifier device is connected with the power device IGBT in parallel to form two sets of short-circuit protection bridge arms; the rectifier is a silicon controlled rectifier; the rectifying devices comprise silicon controlled rectifier rectifying devices D1, D2, D3 and D4, the rectifying devices D1 and D2 are connected in series, D3 and D4 are connected in series, and the rectifying devices and the D3 and the D4 are respectively connected with IGBT bridge arms in parallel; the support capacitor comprises a support capacitor C13 and a support capacitor C14, and the support capacitor C13 and the support capacitor C14 are connected with the power device IGBT in parallel; the clamp diode comprises D11, D12, D21, D22; the power device IGBT comprises a 1# IGBTA1, a 1# IGBTA2, a 1# IGBTA3, a 1# IGBTA4, a 2# IGBTA1, a 2# IGBTA2, a 2# IGBTA3 and a 2# IGBTA4, wherein the 1# IGBTA2 and the 1# IGBTA3 are arranged between the 1# IGBTA1 and the 1# IGBTA4, and the 2# IGBTA2 and the 2# IGBTA3 are arranged between the 2# IGBTA1 and the 2# IGBTA 4; the clamping diodes D11 and D12 are connected in series and then connected in parallel at two ends of the power devices 1# IGBTA2 and 1# IGBTA3, the clamping diodes D21 and D22 are connected in series and then connected in parallel at two ends of the power devices 2# IGBTA2 and 2# IGBTA3, and the added rectifying devices have current flowing only after the IGBT blocking trigger pulse.
2. The protection device for the short-circuit current rectifying device of the bidirectional converter as claimed in claim 1, wherein the impedance value of the connecting DC bus of the rectifying devices D1, D2, D3 and D4 is less than 0.1m Ω.
3. The protection device for the short-circuit current rectifying device of the bidirectional converter as claimed in claim 2, wherein the internal resistance r of the rectifying devices D1, D2, D3 and D4T＝0.253mΩ。
4. The protection device for the short-circuit current rectifying device of the bidirectional converter as claimed in claim 3, wherein the rectifying device is connected in a manner of direct crimping of 3mm copper bars, so that the reliability of crimping is ensured.
5. The protection device for the short-circuit current rectifying device of the bidirectional converter as claimed in claim 4, wherein the operation steps are as follows: step 1, when the bidirectional converter normally works, power devices IGBT, namely 1# IGBTA1-1# IGBTA4, 2# IGBTA1-2# IGBTA4, clamping diodes D11, D12, D21 and D22, and supporting capacitors C13 and C14 trigger the power devices to complete direct current voltage stabilization output, direct current energy feedback and system reactive compensation; step 2, protecting a locking pulse by IGBT (insulated gate bipolar translator), namely 1# IGBTA1-1# IGBTA4 and 2# IGBTA1-2# IGBTA4 when short-circuit fault occurs; step 3, short-circuit faults on the direct-current side are not removed, and short-circuit current is provided by the rectifying devices D1-D4 and the IGBT freewheeling diode in parallel; and 4, the internal resistance of the loop of the rectifying devices D1-D4 is far smaller than that of the IGBT freewheeling diode, most of short-circuit current flows through the loop of the rectifying devices D1-D4, and the IGBT freewheeling diode only bears small current.
CN201611116262.XA 2016-12-07 2016-12-07 Protector for short-circuit current rectifier of bidirectional converter Active CN106655819B (en)

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CN109698496A (en) * 2017-10-20 2019-04-30 株洲中车时代电气股份有限公司 A kind of rail traffic tractive power supply system and control method
CN109188177B (en) * 2018-10-01 2023-12-19 江苏国传电气有限公司 High-power NPC three-level inverter short-circuit current on-line detection system
CN110474550B (en) * 2019-08-21 2020-11-10 阳光电源股份有限公司 Flying capacitor type NPC three-level topology

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CN102394557A (en) * 2011-09-06 2012-03-28 清华大学 Hybrid parallel type high-voltage direct current traction power supply current transformer and control method thereof
CN102709994A (en) * 2012-06-06 2012-10-03 上海煦达新能源科技有限公司 Charge-discharge two-way power converter for battery for electric car

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