Short-time super-large current generating test device and test method based on energy storage technology

Abstract

The present application belongs to the technical field of high-voltage current transformer test equipment, and particularly relates to a short-time super-large current generation test device and a test method. In view of the fact that the existing short-time super-large current generation test device cannot meet the super-large current test, the present application adopts the following technical scheme: a short-time super-large current generation test device based on energy storage technology, comprising: an AC voltage regulating source; a booster AC / DC conversion module; a high-voltage charging and discharging module, comprising a plurality of AC contactors, a rectifier circuit, a DC high-voltage switch, a circuit breaker and a thyristor; an energy storage capacitor bank; a coaxial type non-leakage inductor riser; a waveform acquisition and processing module; a test control module for controlling the AC voltage regulating source, the high-voltage charging and discharging module, the riser and the waveform acquisition and processing module; the copper column, the bottom copper plate, the side copper bar and the top copper plate of the riser are connected in sequence and used for super-large current wiring. The present application can output short-time super-large current and test the rated dynamic and stable current of the current transformer.

Description

TECHNICAL FIELD

[0001] The present application belongs to the technical field of high-voltage current transformer test equipment, and particularly relates to a short-time super-large current generation test device and a test method based on energy storage technology. BACKGROUND

[0002] The current transformer bears the important role of transmitting the primary and secondary current information, and the stability and reliability of the current transformer are the guarantee for the safe operation of the power system, so the reliability of the current transformer is concerned, and the calibration of the current transformer is more and more standardized. At the same time, due to the development of ultra-high voltage power transmission, the current transformer needs to meet higher voltage / current detection, which also puts forward higher requirements for the detection of the current transformer.

[0003] The short-time super-large current generation test device is mainly used for rated dynamic stability current (Idyn) test of the current transformer. The standard value of the rated dynamic stability current (Idyn) is 2.5 times of the rated short-time thermal current test (Ith), Ith = 150Ip, then Idyn = 2.5 * 150Ip = 375Ip (Ip is the rated primary current of the current transformer), the dynamic stability test should be carried out under the condition of short-circuiting the secondary winding, and the peak value of the applied primary current is at least one wave crest not less than the rated dynamic stability current (Idyn). The principle diagram of the rated dynamic stability current test of the current transformer can be referred to Figure 1 . In the figure, TN is a large current sampling standard device (the device selects a flexible coil), TX is a tested current transformer, P1 and P2 are large current winding outlet terminals, S1 and S2 are large current sampling secondary signal ends, 1S1, 1S2, 2S1 and 2S2 are tested current transformer secondary winding outlet terminals.

[0004] When the rated dynamic stability current of the current transformer is tested, a short-time large current generation device is needed to generate a short-time large current. The short-time large current generation device includes an energy storage capacitor, a current riser, a control device and a signal acquisition calculator.

[0005] The basic manufacturing process of the existing current transformer test current riser is as follows: first, the appearance of the current riser core is inspected to ensure that the surface of the core is clean, free of damage, scratches, dirt and other adverse phenomena; second, the current riser core is wound with insulating paper and wrapped with insulating tape; third, the current riser core is wound with enameled wire, and the winding is provided with an insulating sleeve; and finally, the current riser core and the coil are fixed in the case, and the joints are arranged on the case. The main structure of the existing current transformer test current riser is the core, insulating paper, insulating tape, enameled wire coil, coil insulation and case. In use, the large current wire passes through the center hole of the case and the core.

[0006] The existing current transformer test current riser has the following disadvantages: 1. The core magnetic circuit is open, the leakage resistance is large, the power utilization rate is low, and when a large current needs to be generated, the core size is large; 2. The wiring mode of the primary input terminal connected with the regulating power source is fixed, the proportion is fixed, the flexibility is low, and the applicability is not high; 3. The current rising capacity is weak, and it is difficult to meet the test needs of super large current (peak value 50kA) or more.

[0007] The Chinese invention patent application with publication number CN107493092A discloses a large pulse current generating device and a control method thereof, which comprises a main power supply AC contactor, a voltage regulator, a step-up transformer, a rectifier bridge, a filter capacitor, an AC contactor, a voltmeter, an energy storage capacitor, an automatic controller, an electronic switch, and a sampling resistor. The main power supply AC contactor input end is connected with the power grid to obtain electric energy. The scheme disclosed in the application can provide a standard pulse source for current transformer calibration, and has important significance for improving the accurate measurement of the remaining capacity of the battery management system. However, the purpose of the scheme is to improve the estimation accuracy of the remaining capacity of the battery management system, which is one or even multiple orders of magnitude different from the current of the current transformer of the power system. SUMMARY

[0008] The present application aims at the deficiency that the existing short-time super large current generating test device is difficult to meet the needs of super large current test, and provides a short-time super large current generating test device and test method based on energy storage technology. The riser of the device adopts a large current output copper bar closed ring design, has small leakage resistance and strong current rising capacity, and can output a current up to 160kA peak value, thereby meeting the needs of super large current test.

[0009] To achieve the above-mentioned purpose, the present application adopts the following technical scheme: a short-time super large current generating test device, which comprises:

[0010] An AC voltage regulating source connected with AC power;

[0011] A step-up transformer;

[0012] A high-voltage charging and discharging module comprising a plurality of AC contactors, an AC / DC conversion module, a DC high-voltage switch, a circuit breaker and a thyristor;

[0013] An energy storage capacitor group;

[0014] A current riser;

[0015] A waveform acquisition and processing module;

[0016] A test control module for controlling the AC voltage regulating source, the high-voltage charging and discharging module, the current riser and the waveform acquisition and processing module;

[0017] The alternating current is regulated and output by an alternating voltage regulating source, is boosted by a booster, is converted into direct current by an AC / DC conversion module, charges an energy storage capacitor group, is disconnected from a direct current high voltage switch after charging is completed, controls a silicon controlled rectifier to conduct a circuit, is rapidly discharged, and performs a super large current test.

[0018] The booster comprises:

[0019] The copper box comprises a bottom copper plate, a top copper plate and a plurality of side copper bars, the top copper plate is provided with a column hole in the center and a wiring hole in the edge;

[0020] The iron core is annular and arranged in the box;

[0021] The copper core winding is arranged in the box and surrounds the iron core;

[0022] The copper column is located in the center of the iron core and extends out of the box from the upper end of the column hole, and the upper end is provided with a wiring hole;

[0023] The primary input wiring terminal is arranged on the side copper bar and connected with the copper core winding;

[0024] The copper column is insulated from the top copper plate, and the lower end of the copper column is electrically connected with the bottom copper plate;

[0025] The copper column, the bottom copper plate, the side copper bar and the top copper plate are sequentially connected and used for super large current wiring.

[0026] The short-time super large current test device of the application can perform super large current test through the arrangement of the alternating voltage regulating source, the booster, the AC / DC conversion module, the high voltage charging and discharging module, the energy storage capacitor group, the booster, the waveform acquisition and processing module and the test control module; the booster adopts the copper box, the iron core and the copper core winding are arranged in the copper box, the copper column is located in the center of the iron core, the copper box contains the iron core to form a closed ring design, reduces the leakage resistance and improves the current boosting capacity, and can output a current of up to 160kA (peak value).

[0027] As an improvement, the energy storage capacitor group has 4 groups, and each energy storage capacitor group is composed of 15 single capacitors in series.

[0028] As an improvement, the rated voltage of the single capacitor is 0.69kV, the rated current is 144A, and the rated capacity is 100kvar.

[0029] As an improvement, an insulating sleeve is arranged between the copper column and the top copper plate, and the copper column penetrates through the insulating sleeve.

[0030] As an improvement, the insulating sleeve comprises a large diameter part above the top copper plate and a small diameter part in the column hole, a mounting hole is formed on the large diameter part, and the insulating sleeve is fixedly connected with the top copper plate by screws installed from top to bottom.

[0031] As an improvement, a mounting hole is formed in the center of the bottom copper plate, and the lower end of the copper column is positioned in the mounting hole; a mounting hole is formed in the lower end face of the copper column, and the copper column is fixedly connected with the bottom copper plate through the screw installed from bottom to top, and the contact surface is also padded with a pure silver conductive foil with a thickness of 0.2mm, so as to ensure that the copper column and the bottom copper plate are in good contact and fixed reliably.

[0032] As an improvement, each side copper bar includes a plurality of copper strips, and each copper strip is fixedly connected with the bottom copper plate and the top copper plate through a screw, so as to ensure that the copper strip and the bottom copper plate and the top copper plate are in good contact and fixed reliably. When the side copper bar adopts a whole side copper plate (the copper plate is usually 5mm thick), the side copper plate is prone to deformation, and the contact between the side copper plate and the bottom copper plate and the top copper plate is poor, resulting in large impedance, heating and other problems.

[0033] As an improvement, an insulating mounting bottom plate is arranged below the bottom copper plate, and a wheel foot is arranged below the insulating mounting bottom plate.

[0034] As an improvement, the cross section of the copper column is square; and there is a gap between the copper column and the copper core wire winding.

[0035] As an improvement, the one-time input wiring terminal has four groups and is arranged on the four side copper bars; and the copper core wire winding has four groups, and the parameters are the same and are independently arranged.

[0036] As an improvement, the insulating fixing assembly includes a bottom partition plate arranged above the bottom copper plate, a bottom support positioning assembly arranged on the bottom partition plate, a top partition plate arranged below the top copper plate, and a top positioning assembly arranged below the top partition plate, the bottom support positioning assembly positions the lower end of the iron core, and the top positioning assembly positions the upper end of the iron core.

[0037] As an improvement, the bottom support positioning assembly has four groups, each bottom support positioning assembly includes a plurality of support plates and a bottom positioning plate, and the shape of the bottom positioning plate is matched with the shape of the iron core; the top positioning assembly has four groups, each top positioning assembly includes a plurality of pressing plates and a top positioning plate, and the shape of the top positioning plate is matched with the contour of the iron core.

[0038] As an improvement, the high-voltage charging and discharging module includes an AC contactor 1 before the AC voltage regulator, an AC contactor 2 between the voltage booster and the rectifier circuit, and an AC contactor 3 between the voltage regulator and the circuit breaker.

[0039] The short-time super-large current generation test method is applied to the short-time super-large current generation test device, and the short-time super-large current generation test method includes the following steps:

[0040] Step S1: turn on the test circuit of the tested current transformer;

[0041] Step S2, disconnecting the AC contactor, the DC high voltage switch and all the thyristors, closing the AC contactor and the AC contactor, adjusting the output of the voltage regulator, detecting the output voltage and output current of the voltage regulator, reading the large current loop current, calculating the impedance of the current loop, matching the output voltage and the loop large current, resetting the voltage regulator, disconnecting the AC contactor 1 and the AC contactor;

[0042] Step S3, calculating the voltage of the charging capacitor when the required primary current is reached;

[0043] Step S4, obtaining the voltage of the energy storage capacitor according to the calculated value, and charging, the charging voltage reaches 110% of the calculated voltage;

[0044] Step S5, closing the AC contactor, the AC contactor and the DC high voltage switch, disconnecting the AC contactor and all the four-way thyristors, starting the voltage regulator to slowly increase the voltage, charging the energy storage capacitor, when the charging voltage reaches 110% of the required voltage of the test, the voltage regulator is reset, and the AC contactor, the AC contactor and the DC high voltage switch are disconnected;

[0045] Step S6, observing the voltage value of the energy storage capacitor, when the voltage of the energy storage capacitor is consistent with the calculated value, the thyristor is turned on, the super large current of the large current generation test device is generated, the first highest peak value is recorded, and the thyristor is disconnected to cut off the current loop;

[0046] The requirements of thyristor on-off: voltage signal zero-crossing, trigger time error ±10us;

[0047] The requirements of thyristor on-off: current zero-crossing, ensuring the energy balance of the current riser core.

[0048] The short-time super large current generation test device has the advantages that: by setting the AC voltage regulating source, the voltage regulator, the AC / DC conversion module, the high voltage charging and discharging module, the energy storage capacitor group, the current riser, the waveform acquisition and processing module and the test control module, the super large current test can be carried out; the current riser adopts a copper box, the core and the copper core winding are arranged in the copper box, the copper column is located at the center of the core, and the copper box contains the core, forming a closed ring design, reducing the leakage impedance and improving the current rising capacity, and the current up to 160kA (peak) can be output.

[0049] The short-time super large current generation test method is applied to the short-time super large current generation test device, and has all the advantages of the short-time super large current generation test device. BRIEF DESCRIPTION OF DRAWINGS

[0050] Figure 1 It is the principle diagram of the rated dynamic stability current test of the current transformer

[0051] Figure 2It is the general structure block diagram of short-time super-large current generating test device.

[0052] Figure 3 It is the principle diagram of short-time super-large current generating test device.

[0053] Figure 4 It is the structural schematic diagram of the current riser of the embodiment one of the application.

[0054] Figure 5 It is the sectional view of the current riser of the embodiment one of the application.

[0055] Figure 6 It is the structural schematic diagram of the current riser of the embodiment one of the application after hiding some components.

[0056] Figure 7 It is the structural schematic diagram of the current riser of the embodiment two of the application.

[0057] Figure 8 It is the structural schematic diagram of the current riser of the embodiment two of the application after hiding some components.

[0058] In the figure, 1, box body; 11, bottom copper plate; 12, top copper plate; 13, side copper bar; 131, copper strip;

[0059] 2, iron core;

[0060] 3, copper core wire winding;

[0061] 4, copper column;

[0062] 5, primary input wiring terminal;

[0063] 6, insulation sleeve;

[0064] 7, insulation installation base plate;

[0065] 8, wheel foot;

[0066] 9, insulation fixing assembly; 91, bottom partition plate; 92, bottom support positioning assembly; 93, top partition plate; 94, top positioning assembly;

[0067] 10, flexible coil. DETAILED DESCRIPTION

[0068] The technical solutions of the embodiments of the application are explained and described below in combination with the drawings of the embodiments of the application. The following embodiments are only preferred embodiments of the application, and are not all. Based on the embodiments in the embodiments, other embodiments obtained by those skilled in the art without creative labor are within the protection scope of the application.

[0069] Reference Figures 1 to 8The short-time super-large current generating test device of the application comprises:

[0070] An AC voltage regulating source for receiving AC power;

[0071] A booster;

[0072] A high-voltage charging and discharging module comprising a plurality of AC contactors, an AC / DC conversion module, a DC high-voltage switch, a circuit breaker and a thyristor;

[0073] An energy storage capacitor bank;

[0074] A current riser;

[0075] A waveform acquisition and processing module;

[0076] A test control module for controlling the AC voltage regulating source, the high-voltage charging and discharging module, the current riser and the waveform acquisition and processing module;

[0077] The AC power is regulated and output by the AC voltage regulating source, boosted by the booster, converted into DC by the AC / DC conversion module, used to charge the energy storage capacitor bank, and after the charging is completed, the DC high-voltage switch is disconnected, the thyristor is controlled to conduct the circuit, and the super-large current test is performed, the output current is collected and displayed in real time by the waveform acquisition and processing module, and the current waveform is displayed;

[0078] The current riser comprises:

[0079] A copper box comprising a bottom copper plate, a top copper plate and a plurality of side copper bars, the top copper plate is provided with a column hole in the center and a wiring hole in the edge;

[0080] An iron core in the shape of a ring and arranged in the box;

[0081] A copper core wire winding arranged in the box and surrounding the iron core;

[0082] A copper column located at the center of the iron core, the upper end of which extends out of the box from the column hole, and the upper end is provided with a wiring hole;

[0083] A primary input terminal arranged on the side copper bar and connected with the copper core wire winding;

[0084] The copper column is insulated from the top copper plate, and the lower end of the copper column is electrically connected with the bottom copper plate;

[0085] The copper column, the bottom copper plate, the side copper bar and the top copper plate are sequentially connected and used for super-large current wiring.

[0086] The short-time super-large current generating test device of the application can perform super-large current test through the setting of the AC voltage regulating source, the booster, the AC / DC conversion module, the high-voltage charging and discharging module, the energy storage capacitor group, the current riser, the waveform acquisition and processing module and the test control module; the current riser adopts a copper box, the iron core and the copper core winding are arranged in the copper box, the copper column is located at the center of the iron core, the copper box contains the iron core, forming a closed ring design, reducing the leakage resistance and improving the current rising capacity, and the current up to 160kA (peak) can be output.

[0087] Embodiment one

[0088] Referring to Figures 1 to 6 The short-time super-large current generating test device of the embodiment one of the application comprises:

[0089] The AC voltage regulating source is connected to AC power.

[0090] The booster;

[0091] The high-voltage charging and discharging module comprises a plurality of AC contactors, an AC / DC conversion module, a DC high-voltage switch, a circuit breaker and a thyristor.

[0092] The energy storage capacitor group;

[0093] The current riser;

[0094] The waveform acquisition and processing module;

[0095] The test control module controls the AC voltage regulating source, the high-voltage charging and discharging module, the current riser and the waveform acquisition and processing module.

[0096] The AC power is regulated and output by the AC voltage regulating source, is boosted by the booster, is converted into DC by the AC / DC conversion module, is charged to the energy storage capacitor group through the rectifier circuit, the DC high-voltage switch is disconnected after the charging is completed, the thyristor is controlled to be turned on, the circuit is discharged rapidly, the super-large current test is performed, and the current waveform is collected and displayed in real time by the waveform acquisition and processing module.

[0097] In this embodiment, the energy storage capacitor group has four groups, and each energy storage capacitor group is composed of 15 single capacitors in series.

[0098] In this embodiment, the rated voltage of the single capacitor is 0.69kV, the rated current is 144A, and the rated capacity is 100kvar, and a plurality of single capacitors are combined in parallel, which can meet the performance requirements of the short-time super-large current generating device.

[0099] In the embodiment, the energy storage capacitor group is charged by an AC / DC module and a 20A DC current source, which is convenient and fast, has a high efficiency, can provide a short-time super large power instantaneously, and has a maximum output of 975V and an instantaneous discharge current of 2160A. For the rated dynamic stability current tolerance test of a current transformer, the super large current can be generated without additional voltage regulators and transformers.

[0100] In the embodiment, the current riser comprises:

[0101] The box 1 comprises a bottom copper plate 11, a top copper plate 12, and four side copper plates 13. The top copper plate 12 is provided with a column hole in the center and a wiring hole in the edge.

[0102] The iron core 2 is annular and arranged in the box 1.

[0103] The copper core winding 3 is arranged in the box 1 and surrounds the iron core 2.

[0104] The copper column 4 is located in the center of the iron core 2 and extends out of the box 1 from the upper end of the column hole. The upper end of the copper column 4 is provided with a wiring hole.

[0105] The primary input wiring terminal 5 is arranged on the side copper plate 13 and connected to the copper core winding 3.

[0106] The copper column 4 is insulated from the top copper plate 12, and the lower end of the copper column 4 is electrically connected to the bottom copper plate 11.

[0107] In the embodiment, an insulating sleeve 6 is arranged between the copper column 4 and the top copper plate 12, and the copper column 4 passes through the insulating sleeve 6.

[0108] In the embodiment, the insulating sleeve 6 comprises a large-diameter part above the top copper plate 12 and a small-diameter part in the column hole. The large-diameter part is provided with a mounting hole, and the insulating sleeve 6 is fixed to the top copper plate 12 by screws installed from top to bottom. In the figure, the screws connecting the insulating sleeve 6 and the top copper plate 12 are not shown.

[0109] In the embodiment, the bottom copper plate 11 is provided with a mounting hole in the center, and the lower end of the copper column 4 is positioned in the mounting hole. The lower end of the copper column 4 is provided with a mounting hole, and the copper column 4 is fixed to the bottom copper plate 11 by screws installed from bottom to top, which ensures good contact and reliable fixation of the copper column 4 and the bottom copper plate 11. In the figure, the screws connecting the copper column 4 and the bottom copper plate 11 are not shown.

[0110] In this embodiment, each side copper bar 13 includes a plurality of copper bars 131, each copper bar 131 is fixedly connected to the bottom copper plate 11 and the top copper plate 12 by screws, so as to ensure that the copper bar 131 is in good contact with the bottom copper plate 11 and the top copper plate 12 and is fixedly connected. When the side copper bar 13 is made of a whole side copper plate (the copper plate is usually 5mm thick), the side copper plate is prone to deformation, and the contact between the side copper plate and the bottom copper plate 11 and the top copper plate 12 is poor, which leads to problems such as large impedance and heating. In the figure, the screws connecting the copper bar 131 and the bottom copper plate 11 and the top copper plate 12 are not shown.

[0111] In this embodiment, a long hole in the height direction is formed in the copper bar 131 to facilitate installation.

[0112] In this embodiment, an insulating mounting bottom plate 7 is arranged below the bottom copper plate 11, and a wheel foot 8 is arranged below the insulating mounting bottom plate 7.

[0113] In this embodiment, the cross section of the copper column 4 is square; and there is a gap between the copper column 4 and the copper core wire winding 3.

[0114] In this embodiment, the primary input wiring terminal 5 has four groups and is arranged on the four side copper bars 13; the copper core wire winding 3 has four groups and has the same parameters, and the four groups of copper core wire windings 3 are independently arranged. The arrangement of the four groups of independent copper core wire windings 3 and the four groups of primary input wiring terminals 5 is flexible in wiring and can be used in parallel or in series.

[0115] In this embodiment, four groups of wiring holes are arranged on the copper column 4, and four groups of wiring holes are arranged on the top copper plate 12.

[0116] In this embodiment, the insulating fixing assembly 9 is further included, the insulating fixing assembly 9 includes a bottom partition plate 91 arranged above the bottom copper plate 11, a bottom support positioning assembly 92 arranged on the bottom partition plate 91, a top partition plate 93 arranged below the top copper plate 12, and a top positioning assembly 94 arranged below the top partition plate 93. The bottom support positioning assembly 92 positions the lower end of the iron core 2, and the top positioning assembly 94 positions the upper end of the iron core 2.

[0117] In this embodiment, the bottom support positioning assembly 92 has four groups, each bottom support positioning assembly 92 includes a plurality of support plates and a bottom positioning plate, and the shape of the bottom positioning plate is matched with the shape of the iron core 2; the top positioning assembly 94 has four groups, each top positioning assembly 94 includes a plurality of pressing plates and a top positioning plate, and the shape of the top positioning plate is matched with the contour of the iron core 2.

[0118] In this embodiment, the iron core 2 is stacked by a plurality of single iron cores. The single iron core adopts a square structure, which is convenient for installation, fixation and capacity expansion. The material of the single iron core is selected from cold-rolled silicon steel sheets, and the thickness of the strip is 0.27mm; the outer diameter of the iron core is 550*550mm, the inner diameter is 250*250mm, and the height is 200mm.

[0119] The design parameters of the current booster for high-voltage current transformer test in the embodiment are as follows:

[0120] ① Input voltage: AC 0-600V;

[0121] ② Input current: AC 1100A / group, 4 groups can be used in parallel or in series;

[0122] ③ Output voltage: AC 21.5V / turn;

[0123] ④ Maximum output current: 160kA (peak value);

[0124] ⑤ Primary winding turns: 28 turns / group, a total of 4 independent windings;

[0125] ⑥ Center solid cuboid copper column 4: 120*120*1000 (mm);

[0126] ⑦ Upper and lower two-pole square copper plates: 710*710*32 (mm);

[0127] ⑧ Four peripheral outer connecting copper bars: 50*678*5 (mm).

[0128] In the embodiment, the current booster is a coaxial type with no leakage inductance, and the output ends P1 and P2 are the center solid cuboid copper column and the upper-pole top surface copper plate, respectively. There are external connecting wire mounting holes around the output ends P1 and P2, which facilitate the installation and fixation of large current wires nearby during the test, so as to minimize the loop impedance.

[0129] In the embodiment, the four groups of independent windings on the primary side of the current booster have the same parameters, and the test wiring mode of parallel and series connection is adopted, and the parallel connection is used. The maximum output current of P1 and P2 can be 160kA peak value.

[0130] The short-time super-large current generating test device has the advantages that: through cooperation of the AC voltage regulating source, the voltage booster, the AC / DC conversion module, the high-voltage charging and discharging module, the energy storage capacitor group, the current riser, the waveform acquisition and processing module and the test control module, the short-time super-large current is outputted to test the rated dynamic stability current of the current transformer; the capacitor energy storage mode is adopted to solve the problems of high dependence of the super-large current test capacity on the power grid and large impact of the test process on the power grid; the coaxial type non-leakage inductance current riser and the large current busbar design are adopted to shorten the super-large current loop and improve the utilization rate of the core; the copper box 1 is adopted for the current riser, the core 2 and the copper core wire winding 3 are arranged in the copper box 1, the copper column 4 is located at the center of the core 2, the copper box 1 contains the core 2, a closed ring design is formed, the leakage resistance is reduced, and the current rising capacity is improved; the output ends P1 and P2 of the current riser are the center solid cuboid copper column 4 and the upper pole square copper plate respectively; four groups of wiring holes are arranged on the copper column 4 and the top copper plate 12, the large current lead is conveniently installed and fixed near the test position, and the loop impedance is reduced; the flexible coil 10 for super-large current measurement can be fixed and arranged in the current riser to avoid the influence of position change on the accuracy of super-large current measurement; the four groups of independent windings on the primary side are completely same, and the test wiring mode of parallel and series can be used, the maximum peak current of 160kA can be outputted when the windings are used in parallel, and the current rising resolution or precision can be improved when the windings are used in series; the charging power is small, and only 15kVA of charging power is needed, the output is fast, and the charging efficiency is high; the capacitor group can be designed in a movable module, the structure is compact, safe and reliable, and the capacitor group is convenient to carry and expand; the power supply of the short-time super-large current generating test device adopts the capacitor energy storage output mode, is programmed and controlled, is used in cooperation with the compensation capacitor, the maximum test capacity of the system is 3500kVA, and the output capacity is not affected by the power grid; the main loop control of the device adopts the silicon controlled rectifier control to ensure that the voltage and current are turned off at zero; the device can be applied to various short-time super-large current tests of different specifications of current transformers; and the device is designed in a module and has the expandable capacity according to different test requirements.

[0131] Embodiment two

[0132] Referring to Figure 7 and Figure 8 , the short-time super-large current generating test device of the embodiment two of the present application is different from the embodiment one in that the flexible coil 10 is limited.

[0133] In the embodiment, the flexible coil 10 for super-large current measurement is fixed and arranged in the coaxial type non-leakage inductance current riser, and the center solid cuboid copper column P1 penetrates the center, so that the influence of position change on the accuracy of super-large current measurement is avoided.

[0134] The present application also provides a short-time super-large current generating test method, which comprises the following steps:

[0135] Step S1; turn on the test circuit of the subject current transformer;

[0136] Step S2, disconnect AC contactor 2, DC high voltage switch and all thyristors, close AC contactor 1 and AC contactor 3, adjust the output of the voltage regulator, detect the output voltage and output current of the voltage regulator, read the large current loop current, calculate the impedance of the current loop, match the output voltage and the loop large current, reset the voltage regulator, disconnect AC contactor 1 and AC contactor 3;

[0137] Step S3, calculate the voltage of the charging capacitor when the required primary current is reached;

[0138] Step S4, get the voltage of the energy storage capacitor according to the calculated value, and charge, the charging voltage reaches 110% of the calculated voltage;

[0139] Step S5, close AC contactor 1, AC contactor 2 and DC high voltage switch, disconnect AC contactor 3 and all four-way thyristors, start the voltage regulator to slowly increase the voltage, charge the energy storage capacitor, when the charging voltage reaches 110% of the required test voltage, the voltage regulator is reset, and the AC contactor 1, AC contactor 2 and DC high voltage switch are disconnected;

[0140] Step S6, observe the voltage value of the energy storage capacitor, when the voltage of the energy storage capacitor is consistent with the calculated value, turn on the thyristor, the super large current is generated by the large current generation test device, record the first highest peak, and disconnect the thyristor to cut off the current loop;

[0141] Thyristor on requirements: voltage signal zero-crossing, trigger time error ±10μs;

[0142] Thyristor off requirements: current zero-crossing off, ensure the energy balance of the current riser core.

[0143] In step S3, the standard value of the rated dynamic stability current (Idyn) is 2.5 times the rated short-time thermal current (Ith), Ith=150Ip, then Idyn=2.5*150Ip=375Ip (Ip is the rated primary current of the transformer), the dynamic stability test should be carried out under the condition of short-circuiting the secondary winding, and the peak value of the applied primary current is at least one wave crest not less than the rated dynamic stability current (Idyn).

[0144] The above is only a specific embodiment of the present application, but the protection scope of the present application is not limited to this, and those skilled in the art should understand that the present application includes but is not limited to the content described in the above specific embodiment. Any modification that does not deviate from the functional and structural principles of the present application will be included in the scope of the claims.

Claims

1. A short-time super-large current generating test device based on energy storage technology, characterized in that: The short-time super-large current generating test device based on energy storage technology comprises: a voltage regulator connected to AC power; a voltage booster; a high-voltage charging and discharging module comprising a plurality of AC contactors, an AC / DC conversion module, a DC high-voltage switch, a circuit breaker and a thyristor; an energy storage capacitor bank; a current riser; a waveform acquisition and processing module; a test control module for controlling the voltage regulator, the high-voltage charging and discharging module, the current riser and the waveform acquisition and processing module; the voltage regulator, the voltage booster, the AC / DC conversion module, the DC high-voltage switch, the circuit breaker, the thyristor, the energy storage capacitor bank and the current riser are connected in sequence, and the voltage regulator is further connected to the current riser. The AC power is regulated by the voltage regulator, then boosted by the voltage booster, converted into DC by the AC / DC conversion module, and used to charge the energy storage capacitor bank. After the charging is completed, the DC high-voltage switch is disconnected, the thyristor is controlled to conduct the circuit, and the super-large current test is performed. The output current is collected and displayed in real time by the waveform acquisition and processing module. The current riser comprises: a copper box (1) comprising a bottom copper plate (11), a top copper plate (12) and a plurality of side copper bars (13), the top copper plate (12) has a column hole in the center and a wiring hole at the edge; a core (2) in the shape of a ring and arranged in the box (1); a copper core wire winding (3) arranged in the box (1) and surrounding the core (2); a copper column (4) located at the center of the core (2) and having an upper end extending out of the box (1) through the column hole, and a wiring hole at the upper end; a primary input terminal (5) arranged on the side copper bar (13) and connected to the copper core wire winding (3); the copper column (4) is insulated from the top copper plate (12), and the lower end of the copper column (4) is electrically connected to the bottom copper plate (11); the copper column (4), the bottom copper plate (11), the side copper bar (13) and the top copper plate (12) are connected in sequence and used for super-large current wiring.

2. The short-duration, high-current generation test device based on energy storage technology according to claim 1, characterized in that: The energy storage capacitor bank has 4 groups, each of which is composed of 15 single capacitors connected in series.

3. The short-duration, high-current generation test device based on energy storage technology according to claim 2, characterized in that: The rated voltage of the single capacitor is 0.69kV, the rated current is 144A, and the rated capacity is 100kvar.

4. The short-duration, high-current generation test device based on energy storage technology of claim 1, wherein: An insulating sleeve (6) is arranged between the copper column (4) and the top copper plate (12), and the copper column (4) passes through the insulating sleeve (6); a flexible coil (10) for super-large current measurement is fixed inside the current riser, and the copper column (4) passes through the flexible coil (10).

5. The short-duration, high-current generation test device based on energy storage technology according to claim 4, characterized in that: The insulating sleeve (6) comprises a large-diameter part above the top copper plate (12) and a small-diameter part in the column hole, and a mounting hole is formed in the large-diameter part; the insulating sleeve (6) is fixed to the top copper plate (12) by screws installed from top to bottom.

6. The short-duration, ultra-high current generation test device based on energy storage technology of claim 1, wherein: A mounting hole is formed in the center of the bottom copper plate (11), and the lower end of the copper column (4) is positioned in the mounting hole; a mounting hole is formed in the lower end surface of the copper column (4), and the copper column (4) is fixed to the bottom copper plate (11) by screws installed from bottom to top.

7. The short duration, ultra-high current generation test apparatus based on energy storage technology of claim 1, wherein: Each side copper bar (13) includes a plurality of copper bars (131), each copper bar (131) is fixedly connected with the bottom copper plate (11) and the top copper plate (12) by screws; the bottom copper plate (11) is provided below with an insulating mounting bottom plate (7), and the insulating mounting bottom plate (7) is provided below with a wheel foot (8); the copper column (4) has a square cross section; there is a gap between the copper column (4) and the copper core wire winding (3); the primary input terminal (5) has four groups and is arranged on the four side copper bars (13) respectively; the copper core wire winding (3) has four groups and has the same parameters.

8. The short-duration, ultra-high current generation test device based on energy storage technology of claim 1, wherein: The insulating fixing assembly (9) includes a bottom partition plate (91) arranged above the bottom copper plate (11), a bottom support positioning assembly (92) arranged on the bottom partition plate (91), a top partition plate (93) arranged below the top copper plate (12), and a top positioning assembly (94) arranged below the top partition plate (93), wherein the bottom support positioning assembly (92) positions the lower end of the iron core (2), and the top positioning assembly (94) positions the upper end of the iron core (2).

9. The short-duration, high-current generation test device based on energy storage technology according to any one of claims 1 to 8, characterized in that: The high-voltage charging and discharging module includes an AC contactor 1 before the voltage regulator, an AC contactor 2 between the booster and the rectifier circuit, and an AC contactor 3 between the voltage regulator and the circuit breaker.

10. The method for short-time super-large current generation test, applied to the short-time super-large current generation test device based on energy storage technology in claim 9, characterized in that: The short-time super-large current generation test method comprises the following steps: Step S1: turn on the test circuit of the current transformer under test; Step S2: open the AC contactor 2, the DC high-voltage switch and all thyristors, close the AC contactor 1 and the AC contactor 3, adjust the output of the voltage regulator, detect the output voltage and current of the voltage regulator, read the primary current, calculate the impedance of the current rise circuit, match the relationship between the output voltage and the primary current, return the voltage regulator to zero, and open the AC contactor 1 and the AC contactor 3; Step S3: calculate the voltage of the energy storage capacitor when the required primary current is reached; Step S4: charge the energy storage capacitor to 110% of the calculated voltage value; Step S5: close the AC contactor 1, the AC contactor 2 and the DC high-voltage switch, open the AC contactor 3 and all four-way thyristors, start the voltage regulator to slowly increase the voltage, charge the energy storage capacitor, and when the charging voltage reaches 110% of the required test voltage, return the voltage regulator to zero and open the AC contactor 1, the AC contactor 2 and the DC high-voltage switch; Step S6: observe the voltage value of the energy storage capacitor, when the voltage value of the energy storage capacitor is consistent with the calculated value, turn on the thyristor, the super-large current generation test device generates a super-large current, record the first highest peak value, and turn off the thyristor to cut off the current rise circuit; The thyristor on requirement: voltage signal zero-crossing, trigger time error ±10us; The thyristor off requirement: current zero-crossing off, ensure the energy balance of the current riser iron core.

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