A GIS conductive loop resistance test device

Abstract

The utility model discloses a GIS conductive loop resistance test device, which consists of a loop resistance tester and a wireless current clamp; the loop resistance tester has a positive voltage terminal, a positive current terminal, a negative current terminal, and a negative voltage terminal; the wireless current clamp includes a clamp body and an open-and-close measuring jaw, the clamp body includes a shell, a microprocessor, a wireless communication module, and a display screen, and an induction coil is arranged at the open-and-close measuring jaw; the inner side wall of the open-and-close measuring jaw is provided with a groove extending along its length direction, and an airbag strip is embedded in the groove. After being fully inflated, part of the airbag strip extends out of the groove, and a micro air pump is built into the shell of the clamp body, and the air delivery port of the micro air pump is connected to the airbag strip, and the control button of the micro air pump is arranged on the shell of the clamp body. The test device of the utility model can realize various forms of measurement, and the loop resistance can be accurately measured without disassembling the grounding bar, and the test process is simple and efficient.

Description

Technical Field

[0001] The utility model relates to the technical field of electric power detection equipment, in particular to a GIS conductive loop resistance testing device. Background Art

[0002] CIS equipment is widely used in power systems. It is a fully enclosed structure. If defects occur, they cannot be discovered in time. In addition, the equipment often has poor conductor contact, which causes the equipment to heat up during operation, and may eventually cause the equipment to fail to operate normally. The DC voltage drop method is currently the main method used to measure loop resistance. However, the DC voltage drop method requires the removal of the grounding bar, so there are the following problems:

[0003] First, the workload of dismantling the screws between the lead-out conductor of the grounding switch and the grounding bar is huge, the operation is cumbersome, time-consuming and labor-intensive, and the work efficiency is low;

[0004] Second, after the grounding bar is removed, the GIS equipment may induce voltage from surrounding equipment, and the induced voltage is large, which seriously threatens the personal safety of the staff;

[0005] Third, the disassembly of the grounding wire does not meet the on-site safety regulations. If the staff does not reset the grounding bar after the test, the screws are not tightened or the surface is not deoxidized, unreliable grounding will be formed, posing a hidden danger to the safe operation of the power grid;

[0006] Fourth, since the grounding switch does not need to be opened and closed frequently, an oxide film and stains are easily formed at its opening and closing points, which in turn causes excessive contact resistance and has a great impact on the measurement of the DC voltage drop method. Utility Model Content

[0007] The purpose of the utility model is to solve the above problems existing in the prior art and to provide a GIS conductive loop resistance testing device, which can complete the loop resistance testing work without removing the grounding bars on both sides.

[0008] The utility model solves the deficiencies of the above technical problems and adopts the following technical solutions: a GIS conductive loop resistance test device, the GIS conductive loop comprises an A-end grounding bar, a B-end grounding bar, a circuit breaker, an A-end knife switch and a B-end knife switch, the A-end knife switch, the circuit breaker and the B-end knife switch are connected in series to form a GIS main loop, the A-end grounding bar and the B-end grounding bar are respectively connected in parallel between the A-end knife switch and the circuit breaker and between the B-end knife switch and the circuit breaker; the A-end grounding bar and the B-end grounding bar are respectively connected to the GIS main loop with the A-end grounding switch and the B-end grounding switch, and a parallel shunt is formed between the A-end grounding bar and the B-end grounding bar and the equipment housing; the resistance test device comprises a loop resistance tester and an unconnected The loop resistance tester comprises a line current clamp; the loop resistance tester has a positive voltage terminal, a positive current terminal, a negative current terminal, and a negative voltage terminal; the wireless current clamp comprises a clamp body and an open-and-close measuring jaw, the clamp body comprises a shell, a microprocessor and a wireless communication module built in the shell, and a display screen externally mounted on the shell, and an induction coil is arranged at the open-and-close measuring jaw; the inner side wall of the open-and-close measuring jaw is provided with a groove extending along its length direction, an airbag strip is embedded in the groove, and after being fully inflated, part of the airbag strip extends out of the groove, a micro air pump is built into the shell of the clamp body, an air delivery port of the micro air pump is connected to the airbag strip, and a control button of the micro air pump is arranged on the shell of the clamp body.

[0009] As a further optimization of the GIS conductive loop resistance testing device of the utility model: an elastic line is arranged in the airbag strip, and two ends of the elastic line are respectively fixed to the inner walls at both ends of the airbag strip in the inflation deformation direction.

[0010] As a further optimization of the GIS conductive loop resistance test device of the utility model: the loop resistance tester also has a charging hole, a ventilation hole and a speaker hole.

[0011] As a further optimization of the GIS conductive loop resistance test device of the utility model: the loop resistance tester also has a display screen, and the information displayed on the display screen includes battery power, Bluetooth logo, measurement status, wireless probe 1 measurement current, wireless probe 2 measurement current, measured resistance current, measured resistance result and error fault code.

[0012] As a further optimization of the GIS conductive loop resistance testing device of the utility model: the test current of the loop resistance tester is 100A, 200A, and 300A.

[0013] As a further optimization of the GIS conductive loop resistance test device of the utility model: the measuring range of the loop resistance tester is 10μΩ~10mΩ.

[0014] As a further optimization of the GIS conductive loop resistance test device of the utility model: the overcurrent and short-circuit protection of the loop resistance tester is: 330A threshold, 5ms fast cut-off; the overheat protection is: 70°C threshold.

[0015] As a further optimization of the GIS conductive loop resistance testing device of the utility model: the measurement range of the wireless current clamp is: DC0~400A, and the resolution is: DC0.1A.

[0016] The utility model has the following beneficial effects:

[0017] 1. The test device of the utility model can realize various forms of measurement. One is to use the current sensor to directly obtain the actual current of the measured circuit (clamp meter direct measurement mode); the other is to accurately obtain the actual current of the measured circuit by adding one or two current sensors on the basis of the traditional loop resistance meter mode (single-side shunt mode and double-side shunt mode). Correspondingly, according to Ohm's law, the loop resistance of the switch or knife switch equipment can be accurately detected. The loop resistance can be accurately measured without disassembling the grounding bar. The test process is simple and efficient.

[0018] 2. The test device of the utility model has a uniquely designed wireless current clamp. An airbag strip that can be inflated and deflated is arranged on the inner wall of the jaws of the current clamp. When the wireless current clamp is put on the branch line, the airbag strip is inflated by a micro air pump to wrap the line, thereby achieving direct temporary fastening of the wireless current clamp and the line, which facilitates the smooth progress of the detection process. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 This is a schematic diagram of the wiring principle of the test device of the utility model;

[0020] Figure 2 It is a schematic diagram of the structure of the wireless current clamp in the test device of the utility model;

[0021] Figure 3 This is the wiring diagram of the clamp meter direct measurement mode;

[0022] Figure 4 This is the wiring diagram for the unilateral shunt mode;

[0023] Figure 5 This is the wiring diagram for the bilateral shunt mode;

[0024] Markings in the figure:

[0025] A-end ground bar;

[0026] The B-end ground bar;

[0027] breaker;

[0028] A-end knife switch;

[0029] B-end knife switch;

[0030] A-end grounding switch;

[0031] Grounding switch at end B;

[0032] Loop resistance tester;

[0033] Wireless current clamp;

[0034] 9-1, clamp body;

[0035] 9-2, Open and close measuring jaws;

[0036] 9-3, air bag strip;

[0037] 9-4. Elastic thread. DETAILED DESCRIPTION

[0038] In order to better understand the present invention, the content of the present invention is further explained below in conjunction with embodiments, but the content of the present invention is not limited to the following embodiments.

[0039] like Figure 1 As shown, the GIS conductive circuit includes an A-end grounding bar 1, a B-end grounding bar 2, a circuit breaker 3, an A-end knife switch 4 and a B-end knife switch 5. The A-end knife switch 4, the circuit breaker 3 and the B-end knife switch 5 are connected in series to form a GIS main circuit. The A-end grounding bar 1 and the B-end grounding bar 2 are respectively connected in parallel between the A-end knife switch 4 and the circuit breaker 3 and between the B-end knife switch 5 and the circuit breaker 3; the A-end grounding bar 1 and the B-end grounding bar 2 are respectively connected to the GIS main circuit with an A-end grounding switch 6 and a B-end grounding switch 7, and a parallel branch is formed between the A-end grounding bar 1 and the B-end grounding bar 2 and the equipment casing.

[0040] like Figure 2As shown, the resistance test device is composed of a loop resistance tester 8 and a wireless current clamp 9; the loop resistance tester 8 has a positive voltage terminal, a positive current terminal, a negative current terminal, and a negative voltage terminal; the wireless current clamp 9 includes a clamp body 9-1 and an open-close measuring jaw 9-2, the clamp body 9-1 includes a shell, a microprocessor and a wireless communication module built in the shell, and a display screen externally mounted on the shell, and an induction coil is arranged at the open-close measuring jaw 9-2. The current value obtained in the induction coil is sent out in the form of a signal through the wireless communication module. The signal receiver of the loop resistance tester 8 receives the current value signal sent by the signal generator in the wireless current clamp 9 through the wireless communication module, and after being processed by the controller inside the display device, it is displayed in the display window, so that the staff can read the current value in the measured wire. The above-mentioned wireless transmission technology and the technology of obtaining current information through the induction coil are both prior arts, and the more detailed structural details are no longer described, and the prior art can be referred to.

[0041] The loop resistance tester 8 also has a charging port, a vent and a speaker port. The loop resistance tester 8 also has a display screen, and the information displayed on the display screen includes battery power, Bluetooth logo, measurement status, wireless probe 1 measurement current, wireless probe 2 measurement current, measured resistance current, measured resistance result and error fault code.

[0042] The test current of the loop resistance tester 8 is 100A or 200A. The range of the loop resistance tester 8 is 10μΩ~10mΩ. The overcurrent and short circuit protection of the loop resistance tester 8 is: 330A threshold, 5ms fast cut-off; overheat protection is: 70℃ threshold.

[0043] The front panel of the loop resistance tester 8 mainly includes "LCD screen", "print button", "time button", "test button", "running indicator light", "page up button" and "page down button", and "mode selection knob".

[0044] LCD screen: information display interface, please refer to 2.1.3 Screen interface layout below for details;

[0045] Print button: After the measurement is completed or in the history record mode, when the print button is pressed, the Bluetooth printer can print the measurement results or history records. Long press this button to turn on / off the backlight mode;

[0046] Time button: used to switch the measurement time in the traditional mode (100A, 200A); used to switch the time unit that needs to be modified in the time setting mode;

[0047] Test button: Press the test button to start the test. The instrument starts to output the set current. After the current stabilizes, the test automatically starts. After the test is completed, the power output automatically stops. After modifying the time in the time setting mode, press the test button to save the modified value, and two short horizontal bars will be displayed to indicate that the saving is completed;

[0048] Running indicator light: When the test button is pressed, the running indicator light will light up, indicating that the instrument is in the measuring state, and the indicator light will go out when the measurement is finished;

[0049] Mode selection knob: The mode selection knob can select different modes, including measurement selection mode, history recording mode, time setting mode and power off.

[0050] The measurement range of the wireless current clamp 9 is: DC0~400A, and the resolution is: DC0.1A. The inner side wall of the open and close measuring jaw 9-2 is provided with a groove extending along its length direction, and an airbag strip 9-3 is embedded in the groove. After being fully inflated, part of the airbag strip 9-3 extends out of the groove. The shell of the clamp body 9-1 is built with a micro air pump (for example, a MAC20-B type micro air pump can be used), and the air delivery port of the micro air pump is connected to the airbag strip 9-3. The control button of the micro air pump is set on the shell of the clamp body 9-1. An elastic line 9-4 is set in the airbag strip 9-3, and the two ends of the elastic line 9-4 are respectively fixed to the inner walls of the two ends of the airbag strip 9-3 in the inflation deformation direction.

[0051] In the uninflated state, under the action of the elastic line 9-4, the airbag strip 9-3 is pulled into the groove, which will not affect the normal entry of the wire body into the measuring jaw 9-2. When the wire body is placed in the measuring jaw 9-2, the micro air pump is started to inflate the airbag strip 9-3. After the airbag strip 9-3 is inflated, it expands and squeezes the wire body, thereby achieving temporary fastening between the wireless current clamp 9 and the wire body.

[0052] <Test Method>

[0053] like Figure 3 As shown in the figure, when the grounding bar is not disconnected, the three-phase circuits are connected in parallel at the grounding bar. In the clamp meter direct measurement mode, the current I0 actually flowing through the measured circuit can be directly measured using the current clamp meter, and then the circuit resistance R=V / I0 can be calculated using Ohm's law.

[0054] like Figure 4 As shown in the figure, a current test probe is added to the traditional four-wire DC resistance method to measure the current I2 of the parallel branch (shell branch and ground network branch), and then the actual current I0 flowing through the measured circuit can be calculated, I0=I1-I2, and the loop resistance R can be calculated by Ohm's law. x =V / I0=V / (I1-I2).

[0055] The above method is suitable for the case where the grounding points of the GIS grounding switch are wide apart. Adding one more current probe can test the current of the parallel branch. However, when the grounding points are close together and the current is split in two directions, adding one current probe is not enough to measure the current of the parallel branch. In this case, two current probes are needed, such as Figure 5 As shown. Two current probes are used to measure the shunt current I on both sides. 21 and I 22 At this time, the current I0 flowing through the measured circuit can be calculated, I0=I1-I 21 -I 22 , and then use Ohm's law to calculate the measured circuit resistance R x =V / I0=V / (I1-I 21 -I 22 ).

[0056] (1) Ensure that the device under test is in a power-off state before testing;

[0057] (2) All switches, knife switches and grounding switches in the compartment where the equipment under test is located are in the correct state, especially the grounding switch should be

[0058] be in the right state;

[0059] (3) Please use special insulating gloves for electricians when performing wiring operations to prevent induced electricity from endangering personal safety.

[0060] The test device of the utility model can realize various forms of measurement. One is to use a current sensor to directly obtain the actual current of the measured circuit (clamp meter direct measurement mode); the other is to accurately obtain the actual current of the measured circuit by adding one or two current sensors on the basis of the traditional loop resistance meter mode (single-side shunt mode and double-side shunt mode). Correspondingly, according to Ohm's law, the loop resistance of the switch or knife switch equipment can be accurately detected. The loop resistance can be accurately measured without disassembling the grounding bus. The testing process is simple and efficient.

[0061] The above describes the specific embodiments of the present invention. It should be understood that the present invention is not limited to the above specific embodiments, and those skilled in the art can make various modifications within the scope of the claims, which does not affect the essence of the present invention.

Claims

1. A GIS conductive loop resistance test device, the GIS conductive loop comprising an A-end grounding bar (1), a B-end grounding bar (2), a circuit breaker (3), an A-end knife switch (4) and a B-end knife switch (5), the A-end knife switch (4), the circuit breaker (3) and the B-end knife switch (5) being connected in series to form a GIS main loop, the A-end grounding bar (1) and the B-end grounding bar (2) being connected in parallel between the A-end knife switch (4) and the circuit breaker (3) and between the B-end knife switch (5) and the circuit breaker (3), respectively; the A-end grounding bar (1) and the B-end grounding bar (2) being connected to the GIS main loop with an A-end grounding knife switch (6) and a B-end grounding knife switch (7), respectively; and a parallel branch is formed between the A-end grounding bar (1) and the B-end grounding bar (2) and a device housing; characterized in that: The resistance testing device comprises a loop resistance tester (8) and a wireless current clamp (9); the loop resistance tester (8) has a positive voltage terminal, a positive current terminal, a negative current terminal, and a negative voltage terminal; the wireless current clamp (9) comprises a clamp body (9-1) and an open-closed measuring jaw (9-2); the clamp body (9-1) comprises a shell, a microprocessor and a wireless communication module built in the shell, and a display screen externally mounted on the shell; an induction coil is arranged at the open-closed measuring jaw (9-2); the inner side wall of the open-closed measuring jaw (9-2) is provided with a groove extending along its length direction; an airbag strip (9-3) is embedded in the groove; after being fully inflated, part of the airbag strip (9-3) extends out of the groove; a micro air pump is built into the shell of the clamp body (9-1); an air delivery port of the micro air pump is connected to the airbag strip (9-3); a control button of the micro air pump is arranged on the shell of the clamp body (9-1).

2. A GIS conductive loop resistance testing device as claimed in claim 1, characterized in that: An elastic line (9-4) is arranged inside the airbag strip (9-3), and two ends of the elastic line (9-4) are respectively fixed to the inner walls at two ends of the airbag strip (9-3) in the inflation deformation direction.

3. A GIS conductive loop resistance testing device as claimed in claim 1, characterized in that: The loop resistance tester (8) also has a charging hole, a ventilation hole and a speaker hole.

4. A GIS conductive loop resistance testing device as claimed in claim 1, characterized in that: The loop resistance tester (8) also has a display screen, and the information displayed on the display screen includes battery power, Bluetooth logo, measurement status, wireless probe 1 measurement current, wireless probe 2 measurement current, measured resistance current, measured resistance result and error fault code.

5. A GIS conductive loop resistance testing device as claimed in claim 1, characterized in that: The test current of the loop resistance tester (8) is 100A, 200A, or 300A.

6. A GIS conductive loop resistance testing device as claimed in claim 1, characterized in that: The measuring range of the loop resistance tester (8) is 10 μΩ~10 mΩ.

7. A GIS conductive loop resistance testing device as claimed in claim 1, characterized in that: The overcurrent and short-circuit protection of the loop resistance tester (8) is: 330A threshold, 5ms fast cut-off; the overheat protection is: 70℃ threshold.

8. A GIS conductive loop resistance testing device as claimed in claim 1, characterized in that: The wireless current clamp (9) has a measurement range of DC 0-400A and a resolution of DC 0.1A.

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