A fully automatic multifunctional testing device for high-voltage current transformers

Abstract

The present invention discloses a fully automatic multifunctional testing device for high-voltage current transformers, which comprises a high-strength aluminum profile frame. Inside the high-strength aluminum profile frame, a primary side wiring mechanism of the current transformer is installed, an electrical measurement function module is installed, a secondary open-circuit switching mechanism, a secondary side wiring mechanism of the current transformer, a roller conveyor line, a primary current loop switching contactor group and a large-current pneumatic switching device are also installed. The present invention is highly integrated and has a small floor area. The device proposed by this solution can successively carry out polarity inspection, inter-turn insulation test of the secondary winding, basic error measurement, variation test, repeatability test of errors, overload capacity test and residual magnetism influence measurement test on the high-voltage current transformer, integrating the two tests into one. It is applicable to the detection of current transformers.

Description

Technical Field

[0001] The present invention relates to the technical field of high-voltage metering detection, and specifically provides a fully automatic multi-functional test device for high-voltage current transformers. Background Art

[0002] The demand for high-voltage current transformers is increasing as the market expands further, and the detection of high-voltage current transformers is facing increasing pressure. At present, the test methods for checking the winding polarity of high-voltage current transformers, inter-turn insulation tests of secondary windings, overload capacity tests, basic error measurements, variation tests, repeatability tests of errors, and measurement of the influence of residual magnetism are inefficient, and the management and control means are backward. There is no set of safe and effective centralized integrated control solutions. In the current industry, the test devices generally have problems such as single function, separate sets, and incomplete equipment configuration functions. To complete all tests, it is necessary to equip detection devices for each test. During the test, manual handling work is also required between different detection devices, which will inevitably increase the equipment purchase cost and labor cost. At the same time, the switching between different tests requires manual repeated disconnection and connection of wires, which inevitably increases the safety hazards of personnel operation and the test error rate caused by wiring deviation. Summary of the Invention

[0003] The purpose of the present invention is to provide a fully automatic multi-functional test device for high-voltage current transformers.

[0004] To achieve the above purpose, the present invention provides the following technical solution: A fully automatic multi-functional test device for high-voltage current transformers, including a high-strength aluminum profile frame. Inside the high-strength aluminum profile frame, a primary side wiring mechanism of the current transformer is installed, an electrical measurement function module is installed, a secondary open-circuit switching mechanism, a secondary side wiring mechanism of the current transformer, a roller conveyor line, a primary current circuit switching contactor group, and a large-current pneumatic switching device are also installed;

[0005] The primary side wiring mechanism of the current transformer includes a guide rod 1, a guide rod cylinder 1, a P2 contact terminal on the primary side of the current transformer, and a P1 contact terminal on the primary side of the current transformer. One end of the guide rod cylinder 1 is installed on a mounting plate, the mounting plate is installed on the high-strength aluminum profile frame, one end of the guide rod cylinder 1 is connected to one end of the guide rod, a bracket is installed at the bottom of the guide rod, and the P2 contact terminal on the primary side of the current transformer and the P1 contact terminal on the primary side of the current transformer are installed at the bottom of the bracket;

[0006] The electro-measurement function module consists of a demagnetization contactor, a magnetization contactor, a multi-functional switching module, a relay control module, a high-voltage relay module, a programmable power source output voltage to the current booster control contactor, a 1A / 5A switching contactor, a demagnetization resistance module, a secondary winding inter-turn insulation test module, and a switching power supply. The programmable power source output voltage to the current booster control contactor is signal-connected to the current booster, and the secondary winding inter-turn insulation test module is signal-connected to the contact terminals on the secondary side of the current transformer;

[0007] The wiring mechanism on the secondary side of the current transformer includes a guide rod cylinder two, a guide rod two, and contact terminals on the secondary side of the current transformer. One end of the guide rod cylinder two is connected to one end of the guide rod two, the other end of the guide rod two is installed on a fixed frame, the contact terminals on the secondary side of the current transformer are installed on the fixed frame, and the fixed frame is installed on a high-strength aluminum profile frame.

[0008] Preferably, the P2 contact terminal on the primary side of the current transformer and the P1 contact terminal on the primary side of the current transformer are electrically connected through a braided current-carrying wire.

[0009] Preferably, the number of the wiring mechanisms on the primary side of the current transformer is six.

[0010] Preferably, the number of the 1A / 5A switching contactors is two. The demagnetization resistance module is located below the magnetization contactor, the high-voltage relay module is located above the relay control module, the relay control module is located above the secondary winding inter-turn insulation test module, the number of the switching power supplies is two, and the programmable power source output voltage to the current booster control contactor is located above the switching power supply.

[0011] Preferably, the current booster is placed on the ground and is located inside the high-strength aluminum profile frame.

[0012] Preferably, a programmable power source is placed on the ground and is located inside the high-strength aluminum profile frame.

[0013] Preferably, the secondary winding inter-turn insulation test module is signal-connected to the upper computer through a 485 signal line.

[0014] Preferably, springs are provided on both the P2 contact terminal on the primary side of the current transformer and the P1 contact terminal on the primary side of the current transformer.

[0015] The present invention provides a fully automatic multi-functional test device for high-voltage current transformers, having the following beneficial effects:

[0016] 1. High-efficiency integration and small floor area. The device proposed in this solution can sequentially carry out polarity inspection, secondary winding inter-turn insulation test, basic error measurement, variation test, error repeatability test, overload capacity test, and residual magnetism influence measurement test on high-voltage current transformers, integrating the two tests into one.

[0017] 2. High degree of automation. It can achieve automatic transfer, automatic conveying, automatic connection and disconnection of wires, automatic test switching, and automatic uploading of test data for high-voltage current transformers, and complete all tests with centralized management, high reliability, and full automation.

[0018] 3. Low hardware cost. Some test circuits for multiple tests of current transformers can be shared, which greatly improves the reuse of equipment and circuits and reduces the hardware cost.

[0019] 4. Reduced manual participation, safer. The device provided by the present invention can achieve automatic transfer, automatic conveying, automatic connection and disconnection of wires, and automatic test switching of high-voltage current transformers without manual participation, avoiding potential safety hazards in the test.

[0020] 5. High accuracy of test data. The device provided by the present invention adopts a flexible crimping mechanism to achieve reliable contact between the test end and the test object, ensuring the accuracy of test data. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 is a perspective view of the present invention;

[0022] Figure 2 is a perspective view of the primary side wiring mechanism of the current transformer of the present invention;

[0023] Figure 3 is a perspective view of the secondary side wiring mechanism of the current transformer of the present invention;

[0024] Figure 4 is a schematic structural diagram of the electrical measurement function module of the present invention.

[0025] In the figure: 1 high-strength aluminum profile frame, 2 primary side wiring mechanism of the current transformer, 21 first guide rod, 22 first guide rod cylinder, 23-1 P2 contact terminal on the primary side of the current transformer, 23-2 P1 contact terminal on the primary side of the current transformer, 3 electrical measurement function module, 31 demagnetization contactor, 32 magnetization contactor, 33 multi-functional switching module, 34 relay control module, 35 high-voltage relay module, 36 contactor for controlling the output voltage of the programmable power source to the current booster, 37 1A / 5A switching contactor, 38 demagnetization resistance module, 39 secondary winding inter-turn insulation test module, 310 switching power supply, 4 secondary open circuit switching mechanism, 5 secondary side wiring mechanism of the current transformer, 51 second guide rod cylinder, 52 second guide rod, 53 secondary side contact terminal of the current transformer, 6 roller conveyor line, 7 programmable power source, 8 current booster, 9 primary current circuit switching contactor group, 10 standard current transformer, 11 large current pneumatic switching device. DETAILED DESCRIPTION OF THE INVENTION

[0026] Such as Figures 1-4As shown in the figure, the present invention provides a technical solution: a fully automatic multi-functional testing device for high-voltage current transformers, including a high-strength aluminum profile frame 1. Inside the high-strength aluminum profile frame 1, a primary side wiring mechanism 2 of the current transformer is installed. Inside the high-strength aluminum profile frame 1, an electrical measurement function module 3 is installed. Inside the high-strength aluminum profile frame 1, a secondary open-circuit switching mechanism 4, a secondary side wiring mechanism 5 of the current transformer, a roller conveyor line 6, a primary current circuit switching contactor group 9, and a large-current pneumatic switching device 11 are also installed. The booster 8 is placed on the ground and is located inside the high-strength aluminum profile frame 1. A programmable power source 7 is placed on the ground and is located inside the high-strength aluminum profile frame 1.

[0027] The primary side wiring mechanism 2 of the current transformer includes a guide rod 21, a guide rod cylinder 22, a primary side P2 contact terminal 23-1 of the current transformer, and a primary side P1 contact terminal 23-2 of the current transformer. One end of the guide rod cylinder 22 is installed on a mounting plate, and the mounting plate is installed on the high-strength aluminum profile frame 1. One end of the guide rod cylinder 22 is connected to one end of the guide rod 21. A bracket is installed at the bottom end of the guide rod 21. The primary side P2 contact terminal 23-1 and the primary side P1 contact terminal 23-2 of the current transformer are installed at the bottom of the bracket.

[0028] The electrical measurement function module 3 is composed of a demagnetization contactor 31, a magnetization contactor 32, a multi-functional switching module 33, a relay control module 34, a high-voltage relay module 35, a programmable power source output voltage to booster control contactor 36, a 1A / 5A switching contactor 37, a demagnetization resistance module 38, a secondary winding inter-turn insulation test module 39, and a switching power supply 310. The programmable power source output voltage to booster control contactor 36 is signal-connected to the booster 8. The secondary winding inter-turn insulation test module 39 is signal-connected to the secondary side contact terminal 53 of the current transformer. The number of 1A / 5A switching contactors 37 is two. The demagnetization resistance module 38 is located below the magnetization contactor 32. The high-voltage relay module 35 is located above the relay control module 34. The relay control module 34 is located above the secondary winding inter-turn insulation test module 39. The number of switching power supplies 310 is two. The programmable power source output voltage to booster control contactor 36 is located above the switching power supply 310. The secondary winding inter-turn insulation test module 39 is signal-connected to the upper computer through a 485 signal line.

[0029] The secondary side wiring mechanism 5 of the current transformer includes a guide rod cylinder 51, a guide rod 52, and a secondary side contact terminal 53 of the current transformer. One end of the guide rod cylinder 51 is connected to one end of the guide rod 52. The other end of the guide rod 52 is installed on a fixed frame. The secondary side contact terminal 53 of the current transformer is installed on the fixed frame, and the fixed frame is installed on the high-strength aluminum profile frame 1.

[0030] The primary side P2 contact terminal 23-1 of the current transformer and the primary side P1 contact terminal 23-2 of the current transformer are electrically connected through a braided current-carrying wire. Springs are provided on both the primary side P2 contact terminal 23-1 and the primary side P1 contact terminal 23-2 of the current transformer. The number of the primary side wiring mechanisms 2 of the current transformer is six.

[0031] During use, a certain test item can be skipped as needed, and the software completes the settings of information such as the transformation ratio, accuracy, and secondary load of 6 tested current transformers.

[0032] Before the test, the primary current loop switching contactor group 9 or the large-current pneumatic switching device 11 is selectively started according to the transformation ratio of the tested current transformer to form a primary current loop. For example, if the rated primary current of the tested current transformer is 800 A or above, the large-current pneumatic switching device 11 works and the primary current loop switching contactor group 9 does not work; if the rated primary current of the tested current transformer is below 800 A, the large-current pneumatic switching device 11 does not work and the primary current loop switching contactor group 9 works. The primary side wiring mechanism 2 and the secondary side wiring mechanism 5 of the current transformer are pressed down to complete the wiring with the tested current transformer. Except that the secondary open-circuit switching mechanism 4 does not work before the secondary winding inter-turn insulation test, the secondary open-circuit switching mechanism 4 works before the secondary winding inter-turn insulation test, overload capacity test, basic error measurement, variation test, error repeatability test, and residual magnetism influence measurement. When there are still other verification tasks after a certain test is completed, the wiring action can be maintained unchanged. The next test can be directly started. If there are no subsequent test tasks, each wiring mechanism is reset and the contactors are disconnected.

[0033] If the verification task includes the test item of secondary winding inter-turn insulation test, after 6 tested voltage transformers are conveyed and positioned to the verification station through the roller conveyor line, they automatically enter the test process of secondary winding inter-turn insulation test. After the wiring and contactor actions are completed, the program-controlled power source outputs voltage and the contactor 36 for controlling the current booster is closed. The calibration instrument issues a voltage boost command to the program-controlled power source 7. The voltage output by the program-controlled power source 7 reaches the input end of the current booster 8 through the closed contactor 36. The current output by the current booster 8 gradually rises from 0 to 120% of the rated primary current of the tested current transformer and then remains for 1 minute. The secondary winding inter-turn insulation test module 39 collects the open-circuit voltage value on the secondary side of the tested current transformer through the secondary side contact terminal 53, converts it into a digital signal, and transmits it to the upper computer through 485 communication for judgment. When the value is less than the specified value, it is judged as qualified, otherwise it is unqualified.

[0034] If the verification task includes the overload capacity test item, it will automatically enter the overload capacity test process. Each wiring mechanism and the contactor maintain their actions unchanged, and the secondary open-circuit switching mechanism 4 works. After the wiring is completed, the calibrator receives the start overload capacity test instruction from the host computer. The calibrator issues a voltage boost instruction to the programmable power source 7. The output voltage of the programmable power source 7 passes through the closed contactor 36 to the input end of the current booster 8. The output current of the current booster 8 gradually rises to about 5% of the rated primary current of the current transformer under test and remains. The workstations with test specimens are sequentially cut in for error judgment. By judging the error value through the calibrator, it is determined whether the winding polarity of the current transformer under test is correct. If it is correct, the calibrator issues a voltage boost instruction to the programmable power source 7 to boost the voltage, and then the output current of the current booster 8 is maintained at about 150% of the rated primary current of the current transformer under test. The workstations are sequentially cut in for error tests. The test data is analyzed and processed by the calibrator and uploaded to the host computer. The host computer judges whether the data is within the standard limit required by the regulations. If it is within the limit, it is judged that the overload capacity test of the current transformer corresponding to this workstation is qualified; otherwise, it is unqualified.

[0035] If the verification task includes the basic error test item, after the previous test of the current transformer under test is completed, it will automatically enter the basic error test process. The basic error test is carried out by simultaneously boosting the voltage of 6 test specimens to the regulation points - 1% of the rated current (for S-class current transformers), 5%, 20%, 100%, and 120% and maintaining them, and the workstations are sequentially switched for verification. Each wiring mechanism and the contactor maintain their actions unchanged, and the secondary open-circuit switching mechanism 4 also keeps working. After the wiring is completed, the calibrator receives the start basic error test instruction from the host computer. The calibrator issues a voltage boost instruction to the programmable power source 7. The output voltage of the programmable power source 7 passes through the closed contactor 36 to the input end of the current booster 8. The output current of the current booster 8 gradually rises to 1% of the rated primary current of the current transformer under test (for non-S-class current transformers, it starts from 5%) and remains. The workstations are sequentially cut in for error tests. The test data is analyzed and processed by the calibrator and uploaded to the host computer. After the 1% regulation point is completed, the calibrator issues a voltage boost instruction to the programmable power source 7 to boost the voltage, and then the output current of the current booster 8 is maintained at 5% of the rated primary current of the current transformer under test. The workstations are sequentially cut in for error tests. The test data is analyzed and processed by the calibrator and uploaded to the host computer. And so on, the basic error tests at the 20%, 100%, and 120% regulation points are completed, and the test data is analyzed and processed by the calibrator and uploaded to the host computer. The host computer judges whether the data is within the standard limit required by the regulations. If it is within the limit, it is judged that the basic error test of the current transformer corresponding to this workstation is qualified; otherwise, it is unqualified.

[0036] If the verification task includes a variation test item, it will automatically enter the variation test process, and sequentially measure the errors of 6 specimens at the rated current of 5%, 20%, 100%, and 120% regulation points. Then, it will start to sequentially reduce the primary current to the rated current of 120%, 100%, 20%, and 5% regulation points, and the workstations will sequentially switch to measure the errors and perform the verification in sequence. The test data is analyzed and processed by the calibrator and uploaded to the host computer. The host computer determines whether the data difference at the same regulation point meets the required rounding interval. If it is within the rounding interval, it is judged that the variation test of the corresponding current transformer at this workstation is qualified; otherwise, it is unqualified.

[0037] If the verification task includes an error repeatability test item, it will automatically enter the error repeatability test process, and sequentially measure the errors of 6 specimens at the rated current of 20% regulation point. The workstations will sequentially switch to perform the verification 6 times or more (depending on the requirements). The test data is analyzed and processed by the calibrator and uploaded to the host computer. The host computer determines whether the experimental standard deviation of the error is less than 1 rounding interval. If it is within the rounding interval, it is judged that the variation test of the corresponding current transformer at this workstation is qualified; otherwise, it is unqualified.

[0038] If the verification task includes a residual magnetism influence measurement test item, after the previous test of the specimen current transformer ends, it will automatically enter the residual magnetism influence measurement test process, and the primary side wiring mechanism 2 of the current transformer will be reset. A DC current equivalent to 15% of the rated secondary current is passed through the secondary windings of 6 specimen current transformers through the multi-functional switching module 33 for a duration of not less than 2 s to complete the magnetization of the 6 specimen current transformers. Then, the primary side wiring mechanism 2 of the current transformer acts, and according to the basic error test process, the basic error experiment is carried out on the 6 specimens. The test data is analyzed and processed by the calibrator and uploaded to the host computer. The host computer compares this data with the previous basic error, and takes the absolute value of the error change amount as the measurement result of the residual magnetism influence. The host computer determines whether this measurement result is within one-third of the error limit required by the regulation. If so, it is judged that the basic residual magnetism influence measurement test of the corresponding current transformer at this workstation is qualified; otherwise, it is unqualified.

[0039] After the experiment ends, the wiring mechanism will automatically reset.

[0040] In summary, the present invention is highly integrated and has a small floor area. The device proposed in this solution can sequentially carry out polarity inspection, inter-turn insulation test of the secondary winding, basic error measurement, variation test, error repeatability test, overload capacity test, and residual magnetism influence measurement test on the high-voltage current transformer, integrating the two tests into one.

[0041] It has a high degree of automation. It can realize the automatic transfer, automatic conveying, automatic connection and disconnection of wires, automatic test switching, and automatic upload of test data of the high-voltage current transformer, and achieve centralized management, high reliability, and full automation to complete all tests.

[0042] Low hardware cost. Some test circuits for multiple tests of current transformers can be shared, which greatly improves the reuse of equipment and circuits and reduces the hardware cost.

[0043] Reduce manual participation and be safer. The device provided by the present invention can realize the automatic transfer, automatic conveying, automatic connection and disconnection of wires, and automatic switching of tests of high-voltage current transformers without manual participation, avoiding potential safety hazards caused by the tests.

[0044] High accuracy of test data. The device provided by the present invention adopts a flexible crimping mechanism to achieve reliable contact between the test end and the test object, ensuring the accuracy of test data.

Claims

1. A fully automatic multifunctional testing device for high-voltage current transformers, comprising a high-strength aluminum profile frame (1), characterized in that: Inside the high-strength aluminum profile frame (1), a primary side wiring mechanism (2) of the current transformer is installed. Inside the high-strength aluminum profile frame (1), an electrical measurement function module (3) is installed. Inside the high-strength aluminum profile frame (1), a secondary open circuit switching mechanism (4), a secondary side wiring mechanism (5) of the current transformer, a roller conveyor line (6), a primary current circuit switching contactor group (9), and a large-current pneumatic switching device (11) are also installed; The primary side wiring mechanism (2) of the current transformer includes a guide rod 1 (21), a guide rod cylinder 1 (22), a P2 contact terminal (23-1) on the primary side of the current transformer, and a P1 contact terminal (23-2) on the primary side of the current transformer. One end of the guide rod cylinder 1 (22) is installed on a mounting plate, and the mounting plate is installed on the high-strength aluminum profile frame (1). One end of the guide rod cylinder 1 (22) is connected to one end of the guide rod 1 (21). A bracket is installed at the bottom end of the guide rod 1 (21). The P2 contact terminal (23-1) on the primary side of the current transformer and the P1 contact terminal (23-2) on the primary side of the current transformer are installed at the bottom of the bracket; The electrical measurement function module (3) consists of a demagnetization contactor (31), a magnetization contactor (32), a multi-functional switching module (33), a relay control module (34), a high-voltage relay module (35), a contactor for controlling the output voltage of the programmed power source to the current booster (36), a 1A / 5A switching contactor (37), a demagnetization resistance module (38), a secondary winding inter-turn insulation test module (39), and a switching power supply (310). The contactor for controlling the output voltage of the programmed power source to the current booster (36) is signal-connected to the current booster (8). The secondary winding inter-turn insulation test module (39) is signal-connected to the secondary side contact terminal (53) of the current transformer; The secondary side wiring mechanism (5) of the current transformer includes a guide rod cylinder 2 (51), a guide rod 2 (52), and a secondary side contact terminal (53) of the current transformer. One end of the guide rod cylinder 2 (51) is connected to one end of the guide rod 2 (52). The other end of the guide rod 2 (52) is installed on a fixed frame. The secondary side contact terminal (53) of the current transformer is installed on the fixed frame, and the fixed frame is installed on the high-strength aluminum profile frame (1); The P2 contact terminal (23-1) on the primary side of the current transformer and the P1 contact terminal (23-2) on the primary side of the current transformer are electrically connected through a braided current wire; The number of the primary side wiring mechanisms (2) of the current transformer is six.

2. The multifunctional test device for a fully automatic high-voltage current transformer according to claim 1, characterized in that: The number of the 1A / 5A switching contactors (37) is two. The demagnetization resistance module (38) is located below the magnetization contactor (32). The high-voltage relay module (35) is located above the relay control module (34). The relay control module (34) is located above the secondary winding inter-turn insulation test module (39). The number of the switching power supplies (310) is two. The contactor for controlling the output voltage of the programmed power source to the current booster (36) is located above the switching power supply (310).

3. A fully automatic high-voltage current transformer multi-functional test device according to claim 1, characterized in that: The current booster (8) is placed on the ground and is located inside the high-strength aluminum profile frame (1).

4. A fully automatic multifunctional testing device for high-voltage current transformers according to claim 1, characterized in that: A programmable power source (7) is placed on the ground, and the programmable power source (7) is located inside a high-strength aluminum profile frame (1).

5. A fully automatic multifunctional testing device for high-voltage current transformers according to claim 1, characterized in that: The secondary winding inter-turn insulation test module (39) is signal-connected to the host computer through a 485 signal line, and springs are provided on both the transformer primary side P2 contact terminal (23-1) and the transformer primary side P1 contact terminal (23-2).

Images