CN210665910U - Rail transit vehicle converter short circuit test system - Google Patents
Rail transit vehicle converter short circuit test system Download PDFInfo
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- CN210665910U CN210665910U CN201921292244.6U CN201921292244U CN210665910U CN 210665910 U CN210665910 U CN 210665910U CN 201921292244 U CN201921292244 U CN 201921292244U CN 210665910 U CN210665910 U CN 210665910U
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Abstract
The utility model discloses a short circuit test system for a rail transit vehicle converter, which comprises an incoming line unit, a direct current power supply unit and a short circuit test functional unit which are connected in sequence, wherein the input end of the incoming line unit is connected with a test power supply, and the output end of the short circuit test functional unit is connected with the converter to be tested; the short circuit test functional unit comprises a short circuit switch, a short circuit test current limiting element and a plurality of capacitor switching loops; the short-circuit test switch is connected with the short-circuit test current limiting element in series and then connected with the short-circuit switch in parallel; each capacitor switching loop is connected in parallel to the input end of the converter to be tested, and each capacitor switching loop comprises a capacitor and a switching switch which are connected in series. The utility model discloses a test system has advantages such as safe and reliable, improve equipment life-span.
Description
Technical Field
The utility model mainly relates to a rail transit vehicle converter short circuit test system is refered in particular to in the experimental technical field of converter.
Background
The performance requirements of various parts of the rail transit vehicle are very high, the converter is used as a core part of a traction transmission system of the rail transit vehicle, strict test verification needs to be carried out through a test bed when the converter leaves a factory or is overhauled, wherein the short-circuit test condition is very strict, according to the description in GB/T13422-2013 semiconductor power converter electrical test method, after the test power supply is adjusted during the short-circuit test to enable the input voltage and the load current of the converter to be tested to reach rated values, the short-circuit device is closed, the current at a specified measuring point is measured, and whether the action of the fault circuit cut-off and protection device is normal or not is checked. The existing short circuit test system is shown in a block diagram in fig. 1: when the rated working condition is reached, the converter to be tested is directly short-circuited, the instantaneous short-circuit current reaches more than 10kA, the protection device of the converter to be tested acts correspondingly, meanwhile, the whole power supply switching-off is realized by utilizing the breaking short-circuit current capacity of a three-phase alternating-current circuit breaker in an input cabinet (G1) of a test power supply, the mode has too large impact on a power supply grid, part of the test power supply is directly connected to a 380V power supply system, and when the test is carried out, the instantaneous grid voltage of the power supply grid fluctuates greatly, so that the normal office requirements can be influenced; when a short circuit test is carried out, the phenomenon of flash of light is generated in the bulbs in the plant area, and when the three-phase alternating-current circuit breaker is in tripping delay or cannot be tripped, the circuit breaker of the previous stage can be tripped in a protection mode, so that the power supply and distribution of the whole plant area are affected, and the service life of the test power supply device is also affected.
SUMMERY OF THE UTILITY MODEL
The to-be-solved technical problem of the utility model lies in: to the technical problem that prior art exists, the utility model provides a safe and reliable's rail transit vehicle short circuit test system.
In order to solve the technical problem, the utility model provides a technical scheme does:
a short-circuit test system for a rail transit vehicle converter comprises an incoming line unit, a direct-current power supply unit and a short-circuit test functional unit which are sequentially connected, wherein the input end of the incoming line unit is used for being connected with a test power supply, and the output end of the short-circuit test functional unit is used for being connected with the converter to be tested; the short circuit test functional unit comprises a short circuit switch, a short circuit test current limiting element and a plurality of capacitor switching loops; the short-circuit test switch is connected with the short-circuit test current limiting element in series and then connected with the short-circuit switch in parallel; each capacitor switching loop is connected in parallel to the input end of the converter to be tested, and each capacitor switching loop comprises a capacitor and a switching switch which are connected in series.
As a further improvement of the above technical solution:
the short circuit test functional unit also comprises a plurality of voltage sensors and a plurality of current sensors, wherein each voltage sensor is connected in parallel with the input end of the converter to be tested, and each current sensor is connected in series with the input end of the converter to be tested.
The short-circuit test current limiting element comprises a current limiting resistor or a current limiting reactor.
The direct-current power supply unit comprises a soft-start power-on unit, an isolation rectifier transformer unit and a rectification power supply unit which are sequentially connected.
The soft start power-on unit comprises a charging contactor, a charging resistor and a short-circuit contactor; and the charging contactor is connected with the charging resistor in series and then connected with the short-circuit contactor in parallel.
The rectifying power supply unit comprises a plurality of rectifiers and a switch assembly, wherein the input end of the switch assembly is connected with the output end of each rectifier and is used for realizing series connection or/and parallel connection among the rectifiers.
The number of the rectifiers is two, namely a rectifier REC1 and a rectifier REC2, and the switch assembly comprises a switch 2KM1 and a switch 2KM 2; both ends of the 2KM1 are connected to one end of the rectifier REC1 and one end of the rectifier REC2, respectively; one pair of contacts of 2KM2 was located between one end of REC2 and the other end of REC1, and the other pair of contacts of 2KM2 was located between one end of REC1 and the other end of REC 2.
The rectifier is a four-quadrant rectifier or a thyristor rectifier or a diode rectifier.
The isolation rectifier transformer unit includes an isolation transformer.
The inlet wire unit comprises an inlet wire breaker.
Compared with the prior art, the utility model has the advantages of:
the utility model discloses a rail transit vehicle converter short circuit test system adopts short circuit test functional unit initiatively, utilizes the current limiting effect of short circuit test current limiting element, has solved the impact to the electric wire netting when the short circuit test, guarantees when doing the converter short circuit test that electric wire netting and other equipment are not influenced and destroyed, and also plays corresponding protection to test system itself, prolongs the life of equipment; in addition, the current-limiting resistor has the function of a pre-charging resistor, and when the tested converter has no pre-charging resistor, the pre-charging requirement can be met by switching the short-circuit test switch; the test system can meet the requirements of type tests of traction converters and auxiliary converters of all locomotives, motor cars and subways; in addition, the multi-path capacitor switching loop can provide short-circuit current required by short-circuit tests of different converters according to input parameters of the converters, and can meet the requirements on stability and quick recovery of intermediate direct-current voltage when the tested converters are suddenly switched and suddenly cut by 10% -50% of rated load by adjusting capacitance values of the capacitors.
The short circuit test functional unit of the utility model comprises BV1 and BV2 voltage sensors, can detect the voltage values at both sides of the short circuit test current limiting resistor and judge whether the short circuit working condition occurs or not; the system also comprises BC1 and BC2 current sensors, whether a short-circuit working condition occurs or not is judged through current difference values detected by the BC1 and BC2 current sensors, and the incoming line breaker is disconnected when the short-circuit working condition occurs, so that the safety of the equipment is dually ensured; when other tests are carried out, whether the tested converter has an electric leakage fault or not can be judged through the current difference detected by the BC1 and BC2 current sensors, and the safety of personnel and equipment is guaranteed.
Drawings
FIG. 1 is a block diagram of a prior art testing system.
Fig. 2 is a system topology diagram according to an embodiment of the present invention.
Fig. 3 is a circuit diagram of a system according to an embodiment of the present invention.
Fig. 4 is a topology diagram of a dc power supply unit according to an embodiment of the present invention.
Fig. 5 is a circuit diagram of a short circuit test functional unit according to an embodiment of the present invention.
The reference numbers in the figures denote: 1. a wire inlet unit; 2. a direct current power supply unit; 201. soft starting the power-on unit; 202. an isolation rectifier transformer unit; 203. a rectifying power supply unit; 3. a short circuit test function unit; 301. a capacitance switching loop; 4. a control protection unit; 5. a current transformer.
Detailed Description
The invention is further described with reference to the drawings and the specific embodiments.
As shown in fig. 2 to 5, the short-circuit test system for the rail transit vehicle converter of the embodiment includes an incoming line unit 1, a dc power supply unit 2 and a short-circuit test functional unit 3, which are connected in sequence, wherein an input end of the incoming line unit 1 is used for being connected with a test power supply, and an output end of the short-circuit test functional unit 3 is used for being connected with an input end of a converter to be tested 5; the short-circuit test functional unit 3 comprises a short-circuit switch 3KM2, a short-circuit test switch 3KM1, a short-circuit test current limiting element (such as a current limiting resistor or a current limiting reactor) and a plurality of capacitor switching loops 301; the short-circuit switch 3KM2 is connected in series with the input end of the converter 5 to be tested, and the short-circuit test switch 3KM1 is connected in series with the short-circuit test current limiting element and then connected in parallel with the short-circuit switch 3KM 2; each capacitance switching loop 301 is connected in parallel to the input end of the converter to be tested 5, and each capacitance switching loop 301 comprises a capacitor and a switching switch which are connected in series. As shown in fig. 3, the number of the capacitor switching loops 301 in the present embodiment is three, which are respectively 3KM3 and C1, 3KM4 and C2, 3KM5 and C3. Of course, in other embodiments, two, four or more capacitor switching circuits 301 may be provided. Before the short-circuit test is carried out, required capacitance is switched by closing one or more of the switching switches (3KM3, 3KM4 and 3KM 5) so as to store energy to meet the short-circuit current required by the short-circuit test of the tested converter 5; during the test, the short-circuit switch (3KM2) is switched off, and the short-circuit test switch (3KM1) is switched on; when the system reaches the voltage and current required by the converter 5 to be tested, the short-circuit device is closed (for example, a switch in a load loop of the converter 5 to be tested is closed to enable a load to be in short circuit), the capacitor provides instant short-circuit current at the moment, and due to the effect of the short-circuit test current-limiting element, after the short-circuit device is closed, impact on a power grid cannot be caused, and the power supply reliability of the test power supply is guaranteed.
The utility model discloses a rail transit vehicle converter short circuit test system, pioneering adoption short circuit test functional unit 3 utilizes short circuit test current limiting element to solve the impact to the electric wire netting when short circuit test, guarantees when making converter 5 short circuit test that other equipment in the electric wire netting is not influenced and destroyed, and also plays corresponding protection to test system itself, prolongs the life of equipment; in addition, the current-limiting resistor has the function of a pre-charging resistor, and when the tested converter 5 has no pre-charging resistor, the pre-charging requirement can be met by switching the short-circuit test switch; the test system can meet the requirements of type tests of traction converters and auxiliary converters of all locomotives, motor cars and subways; in addition, the multi-path capacitor switching loop 301 can provide short-circuit current required by short-circuit tests of different converters 5 according to input parameters of the converters 5, and can meet the requirements of stability and quick recovery of intermediate direct-current voltage when the tested converters 5 suddenly switch and suddenly cut 10% -50% of rated load by adjusting capacitance values.
In this embodiment, the incoming line unit 1 mainly includes an incoming line breaker QF1, an incoming line protection device, and the like, is used in a three-phase power supply system, provides power access for electrical equipment, can divide and combine currents in normal and fault states, protects and sectionally isolates a power grid, can display a voltage and a current value, has a function of controlling voltage loss protection of the power supply and setting protection parameters, and is configured to carry rated working currents by different cabinet types and turn off and on fault currents by an agreed power supply system.
In this embodiment, the short circuit test functional unit 3 further includes a plurality of voltage sensors and a plurality of current sensors, each voltage sensor is connected in parallel to the input end of the converter to be tested 5, and each current sensor is connected in series to the input end of the converter to be tested 5. As shown in fig. 3 and 5, the voltage sensor includes BV1 and BV2, and the current sensor includes BC1 and BC 2. During a short-circuit test, a large voltage difference (obtained through a difference value between BV1 and BV 2) is formed at two ends of the current-limiting resistor, and a large current difference value is formed between BC1 and BC2, so that the short-circuit test is judged to be performed at the moment, a tripping signal is output to a main circuit breaker of the wire inlet unit 1, and the protection tripping and the safety of the whole system are further guaranteed. The short-circuit test functional unit 3 can provide short-circuit current required by the short-circuit test of the converter 5, limit current output to the capacitor from the front end, judge whether a short-circuit working condition occurs at the rear end, and give a fault signal to break the incoming line breaker QF1 in the incoming line unit 1. In addition, when other tests are performed, whether the current transformer 5 has the leakage fault or not can be judged through the currents detected by the BC1 and the BC 2.
As shown in fig. 2, in this embodiment, the control protection unit 4 is used to implement conventional control and conventional protection for each component, and the specific conventional functions include: controlling the on-off of all switches of the direct-current power supply and software interlocking; controlling the on and off of a rectifier power supply unit, and giving corresponding voltage and current; providing a man-machine operation interface, and modifying and setting bottom layer parameters including acceleration and deceleration time, PID parameter adjustment and the like; the intelligent networking communication function realizes the linkage of the whole test bed equipment; realization of a direct-current power supply protection function and the like; the voltage and current double closed-loop current regulation and current sharing control is adopted, so that the stability and the dynamic response are high, and the transient characteristic is improved.
As shown in fig. 3 and 4, in the present embodiment, the dc power supply unit 2 includes a soft-start power-on unit 201, an isolation rectifier transformer unit 202, and a rectifier power supply unit 203, which are connected in sequence.
As shown in fig. 3, in the present embodiment, the soft-start power-on unit 201 includes a charging contactor 1KM1, a charging resistor, and a shorting contactor 1KM 2; the charging contactor 1KM1 is connected in series with a charging resistor and then connected in parallel with the short-circuit contactor 1KM 2. The soft start power-on unit 201 pre-charges the intermediate direct-current capacitor, the charging contactor and the charging branch where the charging resistor is located are connected in the early stage of power-on, the branch where the short-circuit contactor is located is disconnected, the intermediate direct-current capacitor is slowly pre-charged, and when the intermediate voltage reaches a set value, the short-circuit contactor is connected, and the charging branch is disconnected.
In this embodiment, the isolation rectifier transformer unit 202 includes an isolation transformer ITM1, which is used to convert the power supply voltage into the voltage required by the rectifier power supply unit 203, to realize the voltage conversion and isolation, and to convert the network-side power supply into the secondary-side low voltage, so as to complete the connection function between the rectifier power supply unit 203 and the test power supply; the isolation transformer can restrain higher harmonics, and the iron core still works in a non-saturated state under the combined action of various higher harmonics. The primary side of the isolation transformer is provided with 5 taps which are respectively + 10%, + 5%, 0%, -5%, -10%, tap conversion is carried out in a no-load voltage regulation mode, and five-stage fine adjustment can be carried out on the voltage on the primary side.
In this embodiment, the rectifying power supply unit 203 includes a plurality of rectifiers and a switching element, and an input end of the switching element is connected to an output end of each rectifier, so as to implement series connection or/and parallel connection between the rectifiers, and meet requirements of the current transformer 5 in the rail transit field for different voltage classes. Specifically, the number of rectifiers is two, namely a rectifier REC1 and a rectifier REC2, and the switch assembly comprises a switch 2KM1 and a switch 2KM 2; both ends of the 2KM1 are connected to one end of the rectifier REC1 and one end of the rectifier REC2, respectively; one pair of contacts of 2KM2 was located between one end of REC2 and the other end of REC1, and the other pair of contacts of 2KM2 was located between one end of REC1 and the other end of REC 2. The REC1 and REC2 outputs are connected in series and parallel to form a multiple rectifier; when the rectifier works normally, the rectifiers work in parallel, 2KM2 is switched on, and 2KM1 is switched off; when other rectifiers have faults, the fault rectifiers can be cut off, the rectifiers work in series, 2KM1 is switched on, 2KM2 is switched off, and the rear-end direct-current output voltage is guaranteed to be unchanged. The rectifier is a four-quadrant rectifier, a thyristor rectifier or a diode rectifier, preferably a four-quadrant rectifier. In addition, the number of the rectifiers is not limited, and in other embodiments, the number may be appropriately selected in actual circumstances.
Although the present invention has been described with reference to the preferred embodiments, it is not intended to limit the present invention. The technical solution of the present invention can be used by anyone skilled in the art to make many possible variations and modifications, or to modify equivalent embodiments, without departing from the scope of the technical solution of the present invention, using the technical content disclosed above. Therefore, any simple modification, equivalent change and modification made to the above embodiments by the technical entity of the present invention should fall within the protection scope of the technical solution of the present invention.
Claims (10)
1. The short-circuit test system for the rail transit vehicle converter is characterized by comprising an incoming line unit (1), a direct-current power supply unit (2) and a short-circuit test functional unit (3) which are sequentially connected, wherein the input end of the incoming line unit (1) is connected with a test power supply, and the output end of the short-circuit test functional unit (3) is connected with a converter (5) to be tested; the short-circuit test functional unit (3) comprises a short-circuit switch, a short-circuit test current-limiting element and a plurality of capacitor switching loops (301); the short-circuit switch is connected in series with the input end of the converter (5) to be tested, and the short-circuit test switch is connected in series with the short-circuit test current-limiting element and then connected in parallel with the short-circuit switch; each capacitance switching circuit (301) is connected in parallel to the input end of the converter (5) to be tested, and each capacitance switching circuit (301) comprises a capacitor and a switching switch which are connected in series.
2. The rail transit vehicle converter short circuit test system according to claim 1, characterized in that the short circuit test function unit (3) further comprises a plurality of voltage sensors and a plurality of current sensors, each voltage sensor being connected in parallel to an input of the converter to be tested (5), each current sensor being connected in series to an input of the converter to be tested (5).
3. The rail transit vehicle converter short circuit test system of claim 1, wherein the short circuit test current limiting element comprises a current limiting resistor or a current limiting reactor.
4. The rail transit vehicle converter short circuit test system according to claim 1, 2 or 3, wherein the direct current power supply unit (2) comprises a soft start power-on unit (201), an isolation rectifier transformer unit (202) and a rectification power supply unit (203) which are connected in sequence.
5. The rail transit vehicle converter short circuit test system according to claim 4, wherein the soft start power-on unit (201) comprises a charging contactor, a charging resistor and a short circuit contactor; and the charging contactor is connected with the charging resistor in series and then connected with the short-circuit contactor in parallel.
6. The rail transit vehicle converter short circuit test system according to claim 4, wherein the rectified power supply unit (203) comprises a plurality of rectifiers and a switch assembly, wherein an input end of the switch assembly is connected with an output end of each rectifier for realizing series connection or/and parallel connection between the rectifiers.
7. The rail transit vehicle converter short circuit test system of claim 6, wherein the number of the rectifiers is two, namely a rectifier REC1 and a rectifier REC2, and the switch assembly comprises a switch 2KM1 and a switch 2KM 2; both ends of the 2KM1 are connected to one end of the rectifier REC1 and one end of the rectifier REC2, respectively; one pair of contacts of 2KM2 was located between one end of REC2 and the other end of REC1, and the other pair of contacts of 2KM2 was located between one end of REC1 and the other end of REC 2.
8. The rail transit vehicle converter short circuit test system of claim 6, wherein the rectifier is a four-quadrant rectifier or a thyristor rectifier or a diode rectifier.
9. The rail transit vehicle converter short circuit test system of claim 4, wherein the isolating rectifier transformer unit (202) comprises an isolating transformer.
10. The rail transit vehicle converter short circuit test system according to claim 1 or 2 or 3, characterized in that the incoming line unit (1) comprises an incoming line breaker.
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| Application Number | Priority Date | Filing Date | Title |
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| CN201921292244.6U CN210665910U (en) | 2019-08-09 | 2019-08-09 | Rail transit vehicle converter short circuit test system |
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| CN201921292244.6U CN210665910U (en) | 2019-08-09 | 2019-08-09 | Rail transit vehicle converter short circuit test system |
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Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN111756256A (en) * | 2020-06-29 | 2020-10-09 | 中国铁建重工集团股份有限公司 | Traction power supply equipment |
| CN111994128A (en) * | 2020-08-18 | 2020-11-27 | 中车青岛四方车辆研究所有限公司 | Grid-connected control method and system for auxiliary inverter of urban rail train |
| CN112949062A (en) * | 2021-03-02 | 2021-06-11 | 中车青岛四方车辆研究所有限公司 | Short-circuit protection analysis method and short-circuit test method for urban rail transit traction system |
-
2019
- 2019-08-09 CN CN201921292244.6U patent/CN210665910U/en active Active
Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN111756256A (en) * | 2020-06-29 | 2020-10-09 | 中国铁建重工集团股份有限公司 | Traction power supply equipment |
| CN111994128A (en) * | 2020-08-18 | 2020-11-27 | 中车青岛四方车辆研究所有限公司 | Grid-connected control method and system for auxiliary inverter of urban rail train |
| CN111994128B (en) * | 2020-08-18 | 2022-03-15 | 中车青岛四方车辆研究所有限公司 | Grid-connected control method and system for auxiliary inverter of urban rail train |
| CN112949062A (en) * | 2021-03-02 | 2021-06-11 | 中车青岛四方车辆研究所有限公司 | Short-circuit protection analysis method and short-circuit test method for urban rail transit traction system |
| CN112949062B (en) * | 2021-03-02 | 2022-12-06 | 中车青岛四方车辆研究所有限公司 | Short-circuit protection analysis method and short-circuit test method for urban rail transit traction system |
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Effective date of registration: 20200805 Address after: The age of 412001 in Hunan Province, Zhuzhou Shifeng District Road No. 169 Patentee after: ZHUZHOU CRRC TIMES ELECTRIC Co.,Ltd. Address before: The age of 412001 in Hunan Province, Zhuzhou Shifeng District Road No. 169 Patentee before: ZHUZHOU NATIONAL ENGINEERING RESEARCH CENTER OF CONVERTERS Co.,Ltd. |
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