Device and method for testing transformation ratio of bushing current transformer of oil-immersed transformer

Abstract

The invention provides a transformation ratio testing device for a bushing current transformer of an oil-immersed transformer. The transformation ratio testing device comprises a trigger alarm lamp, an ejector rod, a lock catch structure, a conductive metal tube and a current booster, during testing, oil in an insulating cylinder of the oil-immersed bushing current transformer is emptied, and one end, far away from a trigger alarm lamp, of a conductive metal tube extends into the insulating cylinder and passes through the interior of an iron core; after the conductive metal tube, the base and the current rising instrument are ensured to form a conductive loop by fixing the conductive metal tube in the insulating cylinder through a lock catch structure and keeping the trigger type alarm lamp on normally, a range adjusting button of the current rising instrument is adjusted to generate corresponding output current to be loaded into the conductive loop; the iron core generates corresponding input current which is returned to the current rising instrument, and the transformation ratio is measured by further comparing the ratio of the output current to the input current. According to the invention, before the oil-immersed bushing current transformer is installed and put into operation, the electromagnetic induction transformation ratio can be accurately measured, time and labor are saved, and the safety of a power grid is improved.

Description

Technical Field

[0001] The present invention relates to the technical field of power systems, and in particular to a device and method for testing the transformation ratio of an oil-immersed transformer bushing current transformer. Background Art

[0002] Transformers are the "bridge" connecting power grids of different voltage levels, enabling efficient and flexible transmission and distribution of electrical energy between networks at different voltage levels. In this case, if a transformer fails, a relay protection device is required to promptly isolate the fault. The relay protection device signal comes from the transformer bushing current transformer. Currently, transformer bushing current transformers include cast-type bushing current transformers, oil-immersed bushing current transformers, and gas-insulated bushing current transformers. Their function is to first obtain the current signal of the high-voltage conductor through non-contact electromagnetic induction with high precision, and then, after converting it to a standard signal, connect it to the relay protection device through the secondary winding.

[0003] In the prior art, Figure 1 As shown, the oil-immersed bushing current transformer includes an insulating cylinder 1 / 、Cover 2 / 、Base 3 / , iron core (not shown) and secondary junction box 4 / ; Among them, the cover 2 / Removably mounted on the insulating cylinder 1 / Top of the base 3 / It is made of conductive metal and can be detachably mounted on the insulating cylinder 1 / The bottom end; the core is fixed to the insulating cylinder 1 / The primary coil (not shown) and the secondary winding coil (not shown) are wound thereon; the secondary junction box 4 / Installed on the insulating cylinder 1 / On the outer wall, there are two secondary terminals 5 / , and these two secondary terminals 5 / Extend into the insulating cylinder 1 / At this time, before the oil-immersed bushing current transformer is installed and put into operation, the manufacturer provides the insulation cylinder 1 / After being filled with oil, it is transported to the site for installation and use by the user. However, the user cannot measure the accuracy of the electromagnetic induction ratio of the oil-immersed bushing current transformer on site and often relies on the factory test value. Once there is an accuracy difference after blind installation and commissioning, it needs to be disassembled again, which not only delays the commissioning period and wastes manpower and material resources, but also poses a safety hazard to the power grid.

[0004] Therefore, in order to solve the above problems, there is an urgent need for a transformation ratio test device for oil-immersed transformer bushing current transformer, which can accurately measure the electromagnetic induction ratio before the oil-immersed transformer bushing current transformer is installed and put into operation, which not only saves time and labor, but also improves the safety of the power grid. Summary of the Invention

[0005] The technical problem to be solved by the embodiments of the present invention is to provide a transformation ratio testing device and method for an oil-immersed transformer bushing current transformer, which can accurately measure the electromagnetic induction transformation ratio before the oil-immersed transformer bushing current transformer is installed and put into operation, thereby saving time and labor and improving power grid security.

[0006] In order to solve the above technical problems, the embodiment of the present invention provides a transformation ratio test device for an oil-immersed transformer bushing current transformer, which is used to perform transformation ratio testing on an oil-immersed transformer bushing current transformer before installation and commissioning; the oil-immersed transformer bushing current transformer includes an insulating cylinder, a cover, a base, an iron core, and a secondary junction box; a trigger-type alarm light, a mandrel, a locking structure, a conductive metal tube, and a current riser; wherein,

[0007] The trigger-type alarm light is mounted on one end of the conductive metal tube and forms an insulated connection with the conductive metal tube, and a trigger button preset thereon is located inside the conductive metal tube;

[0008] The push rod is made of insulating material, one end of which extends into the interior of the conductive metal tube and abuts against the trigger button provided on the trigger-type alarm light, and the other end is located outside the conductive metal tube and can be pressed into the interior of the conductive metal tube; wherein, after the end of the push rod away from the trigger button is pressed into the interior of the conductive metal tube, it can be driven to abut against one end of the trigger button to trigger the trigger button to light up the trigger-type alarm light;

[0009] One end of the lock structure is mounted on the outer surface of the conductive metal tube close to the trigger alarm light to form an insulating connection, and the other end is fixed to the top of the insulating cylinder of the oil-immersed bushing current transformer;

[0010] The height of the conductive metal tube is greater than the height of the insulating cylinder of the oil-immersed bushing current transformer; wherein, when the end of the conductive metal tube away from the trigger-type alarm light extends into the insulating cylinder and passes through the iron core of the oil-immersed bushing current transformer, the corresponding end of the push rod can be embedded therein and retracted due to the pressure against the base of the oil-immersed bushing current transformer to expose the entire length of the tube, so that the push rod can contact the base and form a conductive connection;

[0011] The current booster is a current source with adjustable range, which is located outside the insulating cylinder and is provided with two current output terminals, two current input terminals, a range adjustment button and a display screen; wherein, one current output terminal of the current booster is connected to the conductive metal tube via a first electrical conductor and is arranged near the trigger-type alarm light, and the other current output terminal is connected to the base of the oil-immersed bushing current transformer via a second electrical conductor; one current input terminal of the current booster is connected to a preset terminal in the secondary junction box of the oil-immersed bushing current transformer via a third electrical conductor; the other current input terminal of the current booster is connected to another preset terminal in the secondary junction box of the oil-immersed bushing current transformer via a fourth electrical conductor; there are two display screens, one for displaying the real-time output current of the two current output terminals, and the other for displaying the real-time input current of the two current input terminals;

[0012] Among them, when performing a transformation ratio test on the oil-immersed bushing current transformer before installation and commissioning, the oil in the insulating cylinder is emptied, and the end of the conductive metal tube away from the trigger alarm light is first extended into the insulating cylinder from which the oil has been emptied and passed through the inside of the iron core. After the locking structure is used to cooperate and fix the conductive metal tube with the top of the insulating cylinder from which the oil has been emptied, the conductive metal tube is fixed in the insulating cylinder from which the oil has been emptied and the trigger alarm light is kept on to ensure that the conductive metal tube, the base and the current meter form a conductive circuit, and then the range adjustment button of the current meter is adjusted to generate an output current of corresponding size and load it into the conductive circuit, so that the iron core generates a corresponding input current based on the current magnetic field effect and transmits it back to the current meter. The transformation ratio of the oil-immersed bushing current transformer is further measured by comparing the ratio between the output current and the input current through the current meter.

[0013] Wherein, the conductive metal tube is made of copper.

[0014] The locking structure includes a clamp, four insulating rods and four hooks;

[0015] The inner side of the clamp is sleeved and fixed on the outer surface of the conductive metal tube, and the outer side thereof is fixed with the four insulating rods at a certain angle;

[0016] The four hooks are respectively installed on one end of the four insulating rods away from the clamp, and are respectively matched and fixed with the four corresponding through holes preset at the top of the insulating cylinder;

[0017] Among them, when the conductive metal tube stands upright in the middle of the insulating cylinder and the top rod is against the base, the four hooks are respectively buckled into the four through holes preset on the top of the insulating cylinder, driving the top rod to press against the base and retract into the conductive metal tube, so that the conductive metal tube is fixed in the insulating cylinder and directly contacts with the base to form an electrical connection, and then forms a conductive loop with the current riser, and triggers the trigger button to light up the trigger alarm light.

[0018] The certain angle pattern is arranged at equal intervals of 90 degrees.

[0019] The output current generated by the current booster is adjusted by the range adjustment button to increase in a certain range step value.

[0020] Wherein, the trigger-type alarm light is a colorful trigger-type LED light.

[0021] An embodiment of the present invention further provides a method for testing the ratio of an oil-immersed transformer bushing current transformer, which is implemented on the aforementioned oil-immersed transformer bushing current transformer testing device. The method comprises the following steps:

[0022] Detecting the completion of preparatory matters of the oil-immersed transformer bushing current transformer ratio test device; wherein the preparatory matter is that the conductive metal tube and the current riser in the oil-immersed transformer bushing current transformer ratio test device have formed a conductive loop with the base of the oil-immersed transformer bushing current transformer, which is achieved by detecting whether a triggerable alarm light in the oil-immersed transformer bushing current transformer ratio test device remains permanently lit; if it is detected that the triggerable alarm light remains permanently lit, it is determined that the preparatory matter has been completed; conversely, if it is detected that the triggerable alarm light remains off or flashing, it is determined that the preparatory matter has not been completed;

[0023] After it is detected that the preparations have been completed, the range adjustment button of the current booster is periodically adjusted to generate an output current of corresponding magnitude to be loaded into the conductive circuit, and the corresponding input current collected after each periodic adjustment of the output current and transmitted back to the current booster by the iron core of the oil-immersed transformer bushing current transformer is obtained, and further the transformation ratio of the oil-immersed bushing current transformer is measured based on the ratio obtained by comparing the output current and the input current of the same cycle on the current booster.

[0024] Wherein, the method further comprises:

[0025] The output current generated by the current booster is adjusted to increase in a certain range of step values.

[0026] Wherein, the method further comprises:

[0027] The transformation ratio of the oil-immersed bushing current transformer measured each time is compared with the preset manufacturer value of the oil-immersed bushing current transformer, and the eligibility of the oil-immersed bushing current transformer is judged according to the comparison result.

[0028] The implementation of the embodiments of the present invention has the following beneficial effects:

[0029] Before performing a transformation ratio test on an oil-immersed bushing current transformer before installation and commissioning, the present invention performs preparations for determining whether a conductive metal tube, a base of the oil-immersed bushing current transformer and a current riser form a conductive loop by judging whether a trigger-type alarm light on the conductive metal tube remains constantly on. After the preparations are completed, an output current of a corresponding magnitude is generated by adjusting a range adjustment button of the current riser to be loaded into the conductive loop and an input current transmitted back by the iron core based on the current magnetic field effect is collected. The transformation ratio of the oil-immersed bushing current transformer is quickly measured by further comparing the ratio between the two. Thus, the electromagnetic induction transformation ratio can be accurately measured before the oil-immersed bushing current transformer is installed and commissioned, which not only saves time and effort but also improves the safety of the power grid. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, without paying any creative work, other drawings obtained based on these drawings still fall within the scope of the present invention.

[0031] Figure 1 This is a simplified structural diagram of an oil-immersed bushing current transformer in the prior art;

[0032] Figure 2 This is a connection structure diagram of a turns ratio test device for an oil-immersed transformer bushing current transformer provided in an embodiment of the present invention when performing a turns ratio test on an oil-immersed transformer bushing current transformer;

[0033] Figure 3 The present invention provides a flowchart of a method for testing the turns ratio of an oil-immersed transformer bushing current transformer in an embodiment of the present invention. DETAILED DESCRIPTION

[0034] In order to make the objectives, technical solutions and advantages of the present invention more clear, the present invention will be described in further detail below with reference to the accompanying drawings.

[0035] like Figure 2As shown in the figure, an oil-immersed transformer bushing current transformer ratio test device is proposed in an embodiment of the present invention, which is used to perform a ratio test on an oil-immersed bushing current transformer before installation and commissioning; the oil-immersed bushing current transformer includes an insulating cylinder 1, a cover, a base 3, an iron core (not shown) and a secondary junction box 4; a trigger-type alarm lamp a1, a top rod a2, a locking structure a3, a conductive metal tube a4 and a current riser a5; wherein,

[0036] The trigger-type alarm light a1 is a colored trigger-type LED light, which is mounted on one end of the conductive metal tube a4 and forms an insulated connection with the conductive metal tube a4. A trigger button (not shown) is located inside the conductive metal tube a4. In one example, the trigger-type alarm light a1 is a red or green trigger-type LED light, and its housing is made of insulating plastic and fixed to the end of the conductive metal tube a4 by adhesive.

[0037] The push rod a2 is made of an insulating material (such as hard plastic). One end of the push rod a2 extends into the interior of the conductive metal tube a4 and abuts against the trigger button provided on the trigger-type alarm light a1. The other end of the push rod a2 is located outside the conductive metal tube a4 and can be pressed into the interior of the conductive metal tube a4. After the end of the push rod a2 away from the trigger button is pressed into the interior of the conductive metal tube a4, it can be driven to abut against one end of the trigger button, triggering the trigger button to illuminate the trigger-type alarm light a1.

[0038] One end of the lock structure a3 is mounted on the outer surface of the conductive metal tube a4 near the trigger alarm light a1 and forms an insulating connection, and the other end is fixed to the top of the insulating cylinder 1 of the oil-immersed bushing current transformer;

[0039] The conductive metal tube a4 is made of copper and is taller than the insulating cylinder 1 of the oil-immersed bushing current transformer. When the end of the conductive metal tube a4, remote from the trigger-type alarm light a1, extends into the insulating cylinder 1 and passes through the iron core of the oil-immersed bushing current transformer, the corresponding end of the embedded push rod a2 retracts due to pressure against the base 3 of the oil-immersed bushing current transformer, thereby exposing the entire length of the tube (i.e., the end remote from the trigger-type alarm light a1) to contact the base 3 of the oil-immersed bushing current transformer and form a conductive connection.

[0040] The current booster a5 is a current source with adjustable range, which is located outside the insulating cylinder 1 of the oil-immersed bushing current transformer and is provided with two current output terminals a51, two current input terminals a52, a range adjustment button a53 and a display screen a54; wherein, one current output terminal a51 of the current booster a5 is connected to the conductive metal tube a4 through a first electrical conductor a61 and is arranged near the trigger alarm light a1, and the other current output terminal a51 is connected to the base 3 of the oil-immersed bushing current transformer through a second electrical conductor a62; one current input terminal a52 of the current booster a5 is connected to the base 3 of the oil-immersed bushing current transformer through a third electrical conductor a61. A wire a63 is connected to a preset terminal 5 in the secondary terminal box 4 of the oil-immersed bushing current transformer. Another current input terminal a52 of the current booster a5 is connected to another preset terminal 5 in the secondary terminal box 4 of the oil-immersed bushing current transformer via a fourth wire a64. Two display screens a54 are provided, one for displaying the real-time output current of the two current output terminals a51, and the other for displaying the real-time input current of the two current input terminals a52. The output current of the current booster a5 is adjusted by the range adjustment button a53 to increase in increments according to a certain range step value.

[0041] Among them, when performing a transformation ratio test on the oil-immersed bushing current transformer before installation and commissioning, the oil in the insulating cylinder 1 of the oil-immersed bushing current transformer is emptied (not shown), and the end of the conductive metal tube a4 away from the trigger alarm light a1 is first extended into the insulating cylinder 1 from which the oil has been emptied and passed through the iron core of the oil-immersed bushing current transformer, and then the locking structure a3 is used to cooperate and fix it with the top of the insulating cylinder 1 from which the oil has been emptied, so that the conductive metal tube a4 is fixed in the insulating cylinder 1 from which the oil has been emptied and the trigger alarm light a1 is kept on to ensure that the conductive metal tube a4, After the base 3 of the oil-immersed bushing current transformer and the current booster a5 form a conductive loop, the range adjustment button a53 of the current booster a5 is adjusted to generate an output current of corresponding magnitude, which is loaded into the conductive loop through the first electrical conductor a61 and the second electrical conductor a62, so that the iron core generates a corresponding input current based on the current magnetic field effect, which is transmitted back to the current booster a5 through the third electrical conductor a63 and the fourth electrical conductor a63. The ratio between the output current and the input current is further compared by the current booster a5 to measure the transformation ratio of the oil-immersed bushing current transformer.

[0042] It should be noted that the oil in the insulating cylinder 1 of the oil-immersed bushing current transformer can be emptied by directly opening the cover above the insulating cylinder 1 of the empty oil-immersed bushing current transformer and then pouring out the oil. At the same time, when the end of the conductive metal tube a4, away from the trigger-type alarm light a1, is inserted into the insulating cylinder 1 from which the oil has been emptied and passes through the interior of the iron core of the oil-immersed bushing current transformer, the cover is not replaced on top of the insulating cylinder 1 of the oil-immersed bushing current transformer, or the cover is replaced on top of the insulating cylinder 1 of the oil-immersed bushing current transformer and a through-hole is provided in the middle to allow the end of the conductive metal tube a4, away from the trigger-type alarm light a1, to be inserted. Furthermore, when the conductive metal tube a4 is fixed in the insulating cylinder 1 from which the oil has been emptied, the trigger-type alarm light a1 and the locking structure a3 provided thereon are preferably located outside the insulating cylinder 1 from which the oil has been emptied.

[0043] It can be understood that the ratio of the oil-immersed bushing current transformer can be accurately measured by comparing the output current to the input current of the current booster a5 multiple times. For example, the first time the range adjustment button a53 of the current booster a5 is adjusted, the output current meter is 120A, and the input current meter is displayed as 1A on the display screen a54; the second time the range adjustment button a53 of the current booster a5 is adjusted, the output current meter is 240A, and the input current meter is displayed as 2A on the display screen a54; the third time the range adjustment button a53 of the current booster a5 is adjusted, the output current meter is 360A, and the input current meter is displayed as 3A on the display screen a54; the fourth time the range adjustment button a53 of the current booster a5 is adjusted, the output current meter is 480A, and the input current meter is displayed as 4A on the display screen a54; the fifth time the range adjustment button a53 of the current booster a5 is adjusted, the output current meter is 600A, and the input current meter is displayed as 5A on the display screen a54. It can be seen that the transformation ratio is 600 / 5, so the test is carried out to see whether it is consistent with the factory value.

[0044] In one embodiment, the locking structure a3 includes a clamp a31, four insulating rods a32 and four hooks a33; wherein,

[0045] The inner side of the clamp a31 is sleeved and fixed on the outer surface of the conductive metal tube a4, and four insulating rods a32 are fixed on the outer side according to a certain angle pattern (such as an arrangement with equal intervals of 90 degrees).

[0046] Four hooks a33 are respectively installed on one end of the four insulating rods a32 away from the clamp a31, and are respectively fixed with four corresponding through holes (not shown) preset on the top of the insulating cylinder 1 of the oil-immersed transformer bushing current transformer;

[0047] Among them, when the conductive metal tube a4 is vertically erected in the middle of the insulating cylinder 1 of the oil-immersed transformer bushing current transformer and the top rod a2 is abutted against the base 3 of the oil-immersed transformer bushing current transformer, four hooks a33 are respectively buckled into the four through holes preset on the top of the insulating cylinder 1 of the oil-immersed transformer bushing current transformer, driving the top rod a2 to press against the base 3 of the oil-immersed transformer bushing current transformer and retract into the conductive metal tube a4, so that the conductive metal tube a4 is fixed in the insulating cylinder 1 of the oil-immersed transformer bushing current transformer and directly contacts the base 3 of the oil-immersed transformer bushing current transformer to form an electrical connection, and then forms a conductive circuit with the current booster a5, and triggers the trigger button to light up the trigger alarm light a1.

[0048] The working method of the transformation ratio testing device of an oil-immersed transformer bushing current transformer in an embodiment of the present invention is as follows: first, the oil in the insulating cylinder 1 of the oil-immersed bushing current transformer is emptied; second, the end of the conductive metal tube a4 away from the trigger alarm light a1 is extended into the insulating cylinder 1 from which the oil has been emptied and passes through the interior of the iron core of the oil-immersed bushing current transformer, and the top rod a2 is abutted against the base 3 of the oil-immersed transformer bushing current transformer; then, the locking structure a3 is matched and fixed with the top of the insulating cylinder 1 from which the oil has been emptied, so that the conductive metal tube a4 is fixed in the insulating cylinder 1 from which the oil has been emptied and the exposed portion of the top rod a2 is retracted. Inside the conductive metal tube a4, the conductive metal tube a4 is in direct contact with the base 3 of the oil-immersed bushing current transformer, and the trigger alarm light a1 is driven to remain on to ensure that the conductive metal tube a4, the base 3 of the oil-immersed bushing current transformer and the current riser a5 form a conductive loop; then, by repeatedly adjusting the range adjustment button a53 of the current riser a5, an output current of corresponding size is generated and loaded into the conductive loop, so that the iron core generates a corresponding input current based on the current magnetic field effect and transmits it back to the current riser a5; finally, the ratio between the output current and the input current each time is compared by the current riser a5 to measure the transformation ratio of the oil-immersed bushing current transformer.

[0049] like Figure 3 As shown in FIG. 1 , a method for testing the ratio of an oil-immersed transformer bushing current transformer is provided in an embodiment of the present invention. The method is implemented on a device for testing the ratio of an oil-immersed transformer bushing current transformer in an embodiment of the present invention. The method includes the following steps:

[0050] Step S1, detecting completion of preparatory matters of the turns ratio test device for the oil-immersed transformer bushing current transformer; wherein the preparatory matters are that the conductive metal tube and the current riser in the turns ratio test device for the oil-immersed transformer bushing current transformer have formed a conductive loop with the base of the oil-immersed transformer bushing current transformer, which is achieved by detecting whether a triggerable alarm light in the turns ratio test device for the oil-immersed transformer bushing current transformer remains permanently on; if it is detected that the triggerable alarm light remains permanently on, it is determined that the preparatory matters are completed; conversely, if it is detected that the triggerable alarm light remains off or flashing, it is determined that the preparatory matters are not completed;

[0051] Step S2: After detecting that the preparatory matters have been completed, periodically adjusting the range adjustment button of the current booster to generate an output current of corresponding magnitude to be loaded into the conductive loop, and obtaining the corresponding input current transmitted back to the current booster by the iron core of the oil-immersed transformer bushing current transformer after each period of adjusting the output current, and further measuring the transformation ratio of the oil-immersed bushing current transformer based on the ratio obtained by comparing the output current and input current of the current booster in the same period.

[0052] Wherein, the method further comprises:

[0053] The output current generated by the current booster is adjusted to increase in a certain range of step values.

[0054] Wherein, the method further comprises:

[0055] The transformation ratio of the oil-immersed bushing current transformer measured each time is compared with the preset manufacturer value of the oil-immersed bushing current transformer, and the eligibility of the oil-immersed bushing current transformer is judged according to the comparison result.

[0056] The implementation of the embodiments of the present invention has the following beneficial effects:

[0057] Before performing a transformation ratio test on an oil-immersed bushing current transformer before installation and commissioning, the present invention performs preparations for determining whether a conductive metal tube, a base of the oil-immersed bushing current transformer and a current riser form a conductive loop by judging whether a trigger-type alarm light on the conductive metal tube remains constantly on. After the preparations are completed, an output current of a corresponding magnitude is generated by adjusting a range adjustment button of the current riser to be loaded into the conductive loop and an input current transmitted back by the iron core based on the current magnetic field effect is collected. The transformation ratio of the oil-immersed bushing current transformer is quickly measured by further comparing the ratio between the two. Thus, the electromagnetic induction transformation ratio can be accurately measured before the oil-immersed bushing current transformer is installed and commissioned, which not only saves time and effort but also improves the safety of the power grid.

[0058] Those skilled in the art will understand that all or part of the steps in the above-mentioned embodiment method can be completed by instructing the relevant hardware through a program, and the program can be stored in a computer-readable storage medium, such as ROM / RAM, a disk, an optical disk, etc.

[0059] The above disclosure is merely a preferred embodiment of the present invention and certainly cannot be used to limit the scope of the present invention. Therefore, equivalent changes made according to the claims of the present invention are still within the scope of the present invention.

Claims

1. A transformation ratio test device for an oil-immersed transformer bushing current transformer, which is used to perform transformation ratio testing on an oil-immersed transformer bushing current transformer before installation and commissioning; the oil-immersed transformer bushing current transformer comprises an insulating cylinder, a cover, a base, an iron core, and a secondary junction box; characterized in that: It includes a trigger alarm light, a top rod, a locking structure, a conductive metal tube and a current riser; among which, The trigger-type alarm light is mounted on one end of the conductive metal tube and forms an insulated connection with the conductive metal tube, and a trigger button preset thereon is located inside the conductive metal tube; The push rod is made of insulating material, one end of which extends into the interior of the conductive metal tube and abuts against the trigger button provided on the trigger-type alarm light, and the other end is located outside the conductive metal tube and can be pressed into the interior of the conductive metal tube; wherein, after the end of the push rod away from the trigger button is pressed into the interior of the conductive metal tube, it can be driven to abut against one end of the trigger button to trigger the trigger button to light up the trigger-type alarm light; One end of the lock structure is mounted on the outer surface of the conductive metal tube close to the trigger alarm light to form an insulating connection, and the other end is fixed to the top of the insulating cylinder of the oil-immersed bushing current transformer; The height of the conductive metal tube is greater than the height of the insulating cylinder of the oil-immersed bushing current transformer; wherein, when the end of the conductive metal tube away from the trigger-type alarm light extends into the insulating cylinder and passes through the iron core of the oil-immersed bushing current transformer, the corresponding end of the push rod can be embedded therein and retracted due to the pressure against the base of the oil-immersed bushing current transformer to expose the entire length of the tube, so that the push rod can contact the base and form a conductive connection; The current booster is a current source with adjustable range, which is located outside the insulating cylinder and is provided with two current output terminals, two current input terminals, a range adjustment button and a display screen; wherein, one current output terminal of the current booster is connected to the conductive metal tube via a first electrical conductor and is arranged near the trigger-type alarm light, and the other current output terminal is connected to the base of the oil-immersed bushing current transformer via a second electrical conductor; one current input terminal of the current booster is connected to a preset terminal in the secondary junction box of the oil-immersed bushing current transformer via a third electrical conductor; the other current input terminal of the current booster is connected to another preset terminal in the secondary junction box of the oil-immersed bushing current transformer via a fourth electrical conductor; there are two display screens, one for displaying the real-time output current of the two current output terminals, and the other for displaying the real-time input current of the two current input terminals; Among them, when performing a transformation ratio test on the oil-immersed bushing current transformer before installation and commissioning, the oil in the insulating cylinder is emptied, and the end of the conductive metal tube away from the trigger alarm light is first extended into the insulating cylinder from which the oil has been emptied and passed through the inside of the iron core. After the locking structure is used to cooperate and fix the conductive metal tube with the top of the insulating cylinder from which the oil has been emptied, the conductive metal tube is fixed in the insulating cylinder from which the oil has been emptied and the trigger alarm light is kept on to ensure that the conductive metal tube, the base and the current meter form a conductive circuit, and then the range adjustment button of the current meter is adjusted to generate an output current of corresponding size and load it into the conductive circuit, so that the iron core generates a corresponding input current based on the current magnetic field effect and transmits it back to the current meter. The transformation ratio of the oil-immersed bushing current transformer is further measured by comparing the ratio between the output current and the input current through the current meter.

2. The turns ratio test device for oil-immersed transformer bushing current transformer according to claim 1, characterized in that: The conductive metal tube is made of copper.

3. The turns ratio test device for oil-immersed transformer bushing current transformer according to claim 2, characterized in that: The locking structure includes a clamp, four insulating rods and four hooks; wherein, The inner side of the clamp is sleeved and fixed on the outer surface of the conductive metal tube, and the outer side thereof is fixed with the four insulating rods at a certain angle; The four hooks are respectively installed on one end of the four insulating rods away from the clamp, and are respectively matched and fixed with the four corresponding through holes preset at the top of the insulating cylinder; Among them, when the conductive metal tube stands upright in the middle of the insulating cylinder and the top rod is against the base, the four hooks are respectively buckled into the four through holes preset on the top of the insulating cylinder, driving the top rod to press against the base and retract into the conductive metal tube, so that the conductive metal tube is fixed in the insulating cylinder and directly contacts with the base to form an electrical connection, and then forms a conductive loop with the current riser, and triggers the trigger button to light up the trigger alarm light.

4. The turns ratio test device for oil-immersed transformer bushing current transformer according to claim 3, characterized in that: The certain angle regularity is an arrangement with equal intervals of 90 degrees.

5. The turns ratio test device for oil-immersed transformer bushing current transformer according to claim 4, characterized in that: The output current generated by the current booster is adjusted by the range adjustment button to increase in accordance with a certain range step value.

6. The turns ratio test device for oil-immersed transformer bushing current transformer according to claim 5, characterized in that: The trigger-type warning light is a colorful trigger-type LED light.

7. A method for testing the transformation ratio of an oil-immersed transformer bushing current transformer, characterized in that: The method is implemented on the transformation ratio testing device of the oil-immersed transformer bushing current transformer according to claim 6, and the method comprises the following steps: Detecting the completion of preparatory matters of the oil-immersed transformer bushing current transformer ratio test device; wherein the preparatory matter is that the conductive metal tube and the current riser in the oil-immersed transformer bushing current transformer ratio test device have formed a conductive loop with the base of the oil-immersed transformer bushing current transformer, which is achieved by detecting whether a triggerable alarm light in the oil-immersed transformer bushing current transformer ratio test device remains permanently lit; if it is detected that the triggerable alarm light remains permanently lit, it is determined that the preparatory matter has been completed; conversely, if it is detected that the triggerable alarm light remains off or flashing, it is determined that the preparatory matter has not been completed; After it is detected that the preparations have been completed, the range adjustment button of the current booster is periodically adjusted to generate an output current of corresponding magnitude to be loaded into the conductive circuit, and the corresponding input current collected after each periodic adjustment of the output current and transmitted back to the current booster by the iron core of the oil-immersed transformer bushing current transformer is obtained, and further the transformation ratio of the oil-immersed bushing current transformer is measured based on the ratio obtained by comparing the output current and the input current of the same cycle on the current booster.

8. The method for testing the turns ratio of an oil-immersed transformer bushing current transformer according to claim 7, wherein: The method further comprises: The output current generated by the current booster is adjusted to increase in a certain range of step values.

9. The method for testing the turns ratio of an oil-immersed transformer bushing current transformer according to claim 8, wherein: The method further comprises: The transformation ratio of the oil-immersed bushing current transformer measured each time is compared with the preset manufacturer value of the oil-immersed bushing current transformer, and the eligibility of the oil-immersed bushing current transformer is judged according to the comparison result.

Images