A non-inductive resistance device, dry capacitor detection system and detection method

Abstract

The present application relates to the technical field of electrical detection, and in particular to a non-inductive resistance device, a dry capacitor detection system and a detection method. The non-inductive resistance device comprises a mounting plate body and a double-stranded reverse resistance wire. The double-stranded reverse resistance wire is arranged on the mounting plate body and is adapted to be electrically connected with the dry capacitor. In the discharge state of the dry capacitor, the double-stranded reverse resistance wire obtains the current output in the discharge state of the dry capacitor and is used to eliminate the inductance generated by itself by using the current. The present application solves the problem that the resistance wire generates inductance when passing through the current, the inductive inductance generated by the resistance wire itself causes the overall inductance value of the entire test device to change, the inductance generated by the wire itself is uncontrollable, and the accuracy of the experimental results is affected, thereby providing a non-inductive resistance device, a dry capacitor detection system and a detection method.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of electrical detection, in particular to a non-inductive resistance device, a dry capacitor detection system and a detection method. BACKGROUND

[0002] As an important power device in the power system, the main role of power electronic capacitors in the power system is to compensate the reactive power of the power system, improve the power factor of the system, improve the voltage quality, reduce the loss of the line, improve the power transmission capacity of the power grid, and ensure the output of the generator and the operation capacity of the equipment. A large number of power capacitors are installed in various voltage and distribution substations and on lines. The correct installation and normal operation of these capacitors will play an important role in ensuring the power supply quality and efficiency of the power system. With the vigorous development of AC and DC transmission technology, the requirements of electrical equipment for supporting capacitors are becoming higher and higher. Not only higher safety, reliability and durability are required, but also light weight, small size and large capacity of a single capacitor, which puts higher requirements on the safety performance of the capacitor itself.

[0003] Since AC and DC transmission projects are operated throughout the year, the system will be greatly disturbed when the project is subjected to lightning, load short circuit or line grounding and other faults. Therefore, capacitors for AC and DC transmission must be able to withstand a large number of impact currents. In the type test of dry capacitors, the short-circuit discharge test is a test that can simulate the impact of current on capacitors during operation. The impact discharge current received by the capacitor is changed through a short-circuit discharge device, so as to investigate the safety performance of the capacitor itself. In GB / T 17702-2021, it is stipulated that power electronic capacitors need to pass 5 times of surge discharge and 1000 times of impact discharge of durability test, and the current value required also needs to be adjusted according to the specifications of the capacitor itself. Therefore, it is urgent to evaluate the impact discharge performance of dry capacitors and to develop a non-inductive resistance device that can adjust and control high-voltage discharge current.

[0004] In the capacitor impact discharge test, the size of the discharge current is mainly affected by the voltage across the capacitor, the capacitance of the capacitor, the loop inductance and the loop resistance. At present, most of the short-circuit discharge devices on the market generally use inductance / voltage regulation method to adjust the discharge current of the capacitor. According to the capacity of the tested capacitor, the discharge current is adjusted by changing the loop inductance and the charging voltage. However, for small-capacity capacitors that require high charging voltage in the test, blindly increasing the loop inductance to reduce the discharge current often cannot achieve good results, and larger inductance coils also occupy more test space, increasing the overall test cost.

[0005] The traditional way to increase the loop resistance is to introduce high-voltage high-resistance conductors, however, the overall resistance of the high-resistance conductors can be adjusted in a small range, and the long resistance conductors will generate an induced potential when passing through the current, and the inductance generated by the resistance conductors themselves will cause the overall inductance value of the entire test device to change, and the inductance generated by the conductors themselves is uncontrollable, which causes the theoretical inductance value to be inconsistent with the actual inductance value in the test process, thereby affecting the theoretical calculation value of the impulse current and the accuracy of the experimental results. SUMMARY

[0006] Therefore, the technical problem to be solved by the present application is to overcome the defects in the prior art that the inductance generated by the resistance conductors themselves will cause the overall inductance value of the entire test device to change, and the inductance generated by the conductors themselves is uncontrollable, which affects the accuracy of the experimental results, thereby providing a non-inductive resistance device, a dry capacitor detection system and a detection method.

[0007] In order to solve the above problems, the present application provides a non-inductive resistance device, comprising:

[0008] a mounting plate body;

[0009] a double-stranded reverse resistance wire, the double-stranded reverse resistance wire is arranged on the mounting plate body, and the double-stranded reverse resistance wire is adapted to be electrically connected with the dry capacitor, in the discharge state of the dry capacitor, the double-stranded reverse resistance wire obtains the current output in the discharge state of the dry capacitor, and is used to eliminate the inductance generated by the current.

[0010] Optionally, the double-stranded reverse resistance wire is a "U" shaped structure located on the opposite sides of the mounting plate body.

[0011] Optionally, the mounting plate body further comprises a fixing plate, and the fixing plate is used to fix the double-stranded reverse resistance wire.

[0012] Optionally, the length of the double-stranded reverse resistance wire is 500-1500mm, the withstand voltage value is 500-1500VDC, and the resistance value is 0.128-0.384Ω.

[0013] Optionally, the number of the double-stranded reverse resistance wire is at least two, and the adjacent double-stranded reverse resistance wires are arranged on the mounting plate body at equal intervals.

[0014] Optionally, the two ends of each double-stranded reverse resistance wire are fixed on the mounting strips on the two sides of the mounting plate body through a fastening stud.

[0015] Optionally, an active connecting piece is arranged between the two adjacent fastening studs, the active connecting piece comprises two round holes for accommodating the fastening studs, and the two adjacent double reverse resistance wires are connected in parallel or series through the active connecting piece to form different resistance values.

[0016] The dry capacitor detection system comprises the non-inductive resistance device, an inductor, a first electrode and an active double electrode, the non-inductive resistance device, the inductor and the first electrode are sequentially connected, the high-voltage electrode of the dry capacitor is connected with the non-inductive resistance device, the low-voltage electrode of the dry capacitor is connected with the first active electrode of the active double electrode, and the first electrode and the first active electrode are correspondingly arranged.

[0017] Optionally, the dry capacitor detection system further comprises a second electrode and a high-voltage power supply, the active double electrode comprises a second active electrode and a double-head air cylinder, two ends of the double-head air cylinder are connected with the second active electrode and the first active electrode respectively, the positive electrode of the high-voltage power supply is connected with the high-voltage electrode of the dry capacitor, the negative electrode of the high-voltage power supply is connected with the second electrode, the low-voltage electrode of the dry capacitor is connected with the second active electrode, and the second electrode and the second active electrode are correspondingly arranged.

[0018] A dry capacitor detection method, in a test state, a discharge current peak value is obtained according to a test standard of the dry capacitor, and a theoretical resistance value is obtained from the following formula:

[0019]

[0020]

[0021]

[0022] Wherein I is the discharge current peak value, L is the loop inductance value, C is the capacitor capacitance value, and R is the loop resistance value, and the resistance value of the non-inductive resistance device is adjusted according to the theoretical resistance value to perform a detection test.

[0023] The technical scheme of the present application has the following advantages:

[0024] 1. The non-inductive resistance device provided by the present application comprises a mounting plate body and double reverse resistance wires arranged on the mounting plate body, the double reverse resistance wires are suitable for being connected with a dry capacitor, in a discharge state of the dry capacitor, the double reverse resistance wires obtain the current output in the discharge state of the dry capacitor, and are used for eliminating the inductance generated by the current to ensure the accuracy of test results. Through the double reverse resistance wires, the inductive inductance generated when the current passes through the resistance is eliminated, and the inductance value in the test is prevented from fluctuating, so that the test results are accurate and reliable.

[0025] 2. The non-inductive resistance device provided by the present application, the double reverse resistance wires are in "U" shape structure on the opposite sides of the mounting plate body, when the current flows, the induced inductance of the two parallel lines of the "U" shape structure will offset each other, eliminating the induced inductance of the double reverse resistance wires.

[0026] 3. The non-inductive resistance device provided by the present application, the mounting plate body further comprises a fixing plate, the fixing plate fixes the double reverse resistance wires, to ensure the stability of the double reverse resistance wires in the test.

[0027] 4. The non-inductive resistance device provided by the present application, the number of the double reverse resistance wires is at least two, the adjacent double reverse resistance wires are arranged on the mounting plate body at equal intervals, having the advantages of neat arrangement and easy maintenance.

[0028] 5. The non-inductive resistance device provided by the present application, the two ends of each double reverse resistance wire are fixed on the mounting strips on the two sides of the mounting plate body through a fastening stud, to realize the fixation of the double reverse resistance wires.

[0029] 6. The non-inductive resistance device provided by the present application, an active connecting piece is further arranged between the two adjacent fastening studs, the active connecting piece comprises two round holes for accommodating the fastening studs, the adjacent double reverse resistance wires are connected in parallel or series through the active connecting piece to form different resistance values, so that the whole non-inductive resistance device has different resistance values, thereby adapting to different tests.

[0030] 7. The dry capacitor detection system provided by the present application, comprising the above non-inductive resistance device, further comprising an inductor coil, a first electrode and an active double electrode, the non-inductive resistance device, the inductor coil and the first electrode are connected with each other in sequence, the high voltage end electrode of the dry capacitor is used for connecting with the non-inductive resistance device, the low voltage end electrode of the dry capacitor is connected with the first active electrode of the active double electrode, and the first electrode and the first active electrode are correspondingly arranged. When in the test state, the first electrode and the first active electrode are connected, the current flowing out of the high voltage end electrode of the dry capacitor passes through the non-inductive resistance device, the inductor coil, the first electrode, the first active electrode in sequence and then reaches the low voltage end electrode of the dry capacitor, to realize the discharge state of the dry capacitor.

[0031] 8. The non-inductive resistance device provided by the present application further comprises a second electrode, a high-voltage power supply, the movable double electrode comprises a second movable electrode and a double-end air cylinder, two ends of the double-end air cylinder are connected with the second movable electrode and the first movable electrode respectively, the positive pole of the high-voltage power supply is used for connecting with the high-voltage end electrode of the dry capacitor, the negative pole of the high-voltage power supply is connected with the second electrode, the low-voltage end electrode of the dry capacitor is used for connecting with the second movable electrode, and the second electrode and the second movable electrode are arranged correspondingly. When the dry capacitor is in a charging state, the second electrode and the second movable electrode are connected, the current flowing out of the positive pole of the high-voltage power supply reaches the high-voltage end electrode of the dry capacitor, and the current flowing out of the negative pole reaches the low-voltage end electrode of the dry capacitor through the second electrode and the second movable electrode. BRIEF DESCRIPTION OF DRAWINGS

[0032] In order to more clearly illustrate the specific embodiments of the present application or the technical solutions in the prior art, the following will briefly introduce the drawings needed to be used in the specific embodiments or prior art description. Obviously, the drawings described below are some embodiments of the present application, and other drawings can also be obtained by those skilled in the art without any creative labor based on these drawings.

[0033] Figure 1 The schematic diagram of the non-inductive resistance device provided in the embodiments of the present application;

[0034] Figure 2 The schematic diagram of the fastening stud and the movable connecting piece provided in the embodiments of the present application;

[0035] Figure 3 The schematic diagram of the fastening stud and the movable connecting piece provided in the embodiments of the present application;

[0036] Figure 4 The schematic diagram of the double reverse resistance wire generating induced inductance when energized provided in the embodiments of the present application;

[0037] Figure 5 The schematic diagram of the dry capacitor detection system in a charging state provided in the embodiments of the present application;

[0038] Figure 6 The schematic diagram of the dry capacitor detection system in a discharging state provided in the embodiments of the present application.

[0039] Explanation of reference numerals: 1, mounting plate body; 2, double reverse resistance wire; 3, fixed plate; 4, mounting strip; 5, nut; 6, movable connecting piece; 7, fastening stud; 8, inductance coil; 9, non-inductive resistance device; 10, dry capacitor; 11, high-voltage power supply; 12, first electrode; 13, first movable electrode; 14, double-end air cylinder; 15, second movable electrode; 16, second electrode. Detailed Implementation

[0040] The technical solution of the present invention will now be clearly and completely described with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0041] In the description of this invention, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing the invention and for simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the invention. Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0042] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0043] Furthermore, the technical features involved in the different embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

[0044] like Figures 1-6 One specific embodiment of the non-inductive resistor device shown includes: a non-inductive resistor device 9, including a mounting plate 1 and 25 double-stranded reverse resistor lines 2 disposed on the mounting plate 1, wherein adjacent double-stranded reverse resistor lines 2 are disposed at equal intervals on the mounting plate 1.

[0045] like Figure 1As shown, each double-stranded reverse resistance wire 2 is in a "U" shape structure located on the opposite sides of the mounting plate body 1. In order to fix the double-stranded reverse resistance wire 2, the opposite sides of the mounting plate body 1 are respectively provided with a fixing plate 3, and the double-stranded reverse resistance wire 2 is fixed on the mounting plate body 1 by the fixing plate 3. The length of the double-stranded reverse resistance wire 2 is 500-1500 mm, the withstand voltage value is 500-1500 VDC, and the resistance value is 0.128-0.384 Ω. Specifically, the length of a single double-stranded reverse resistance wire 2 is 1000 mm, the withstand voltage value is 1000 VDC, and the resistance value is 0.256 Ω. It should be noted that the double-stranded reverse resistance wire can also be selected according to actual test conditions, and other lengths, withstand voltage values and resistance values can be selected. Figure 2 , Figure 3The installation plate body 1 is provided with an installation strip 4 on each of the opposite sides, and each installation strip 4 is provided with 25 fastening studs 7 and 50 nuts 5. The double reverse resistance wire 2 is wound on the fastening stud 7 and connected with the fastening stud 7 through the nuts 5, so as to fix the double reverse resistance wire 2 between the installation strip 4 and the end of the fastening stud 7. One fastening stud 7 is provided with two nuts 5, and the two nuts 5 are provided with a movable connecting piece 6. The movable connecting piece 6 includes two round holes, and one round hole is arranged between the two nuts 5. Since there are multiple double reverse resistance wires 2, the non-inductive resistance device 9 can adjust the resistance value through series connection or parallel connection between the multiple double reverse resistance wires 2. Taking three double reverse resistance wires 2 as an example, when series connection is needed, the first double reverse resistance wire 2 and the second double reverse resistance wire 2 on the front surface of the installation plate body 1 are separated, the movable connecting piece 6 between the first double reverse resistance wire 2 and the second double reverse resistance wire 2 on the back surface of the installation plate body 1 is connected, the movable connecting piece 6 between the second double reverse resistance wire 2 and the third double reverse resistance wire 2 on the front surface of the installation plate body 1 is connected, the second double reverse resistance wire 2 and the third double reverse resistance wire 2 on the back surface of the installation plate body 1 are separated, and the current generated by the dry capacitor 10 in the discharge state enters the first double reverse resistance wire 2 on the front surface of the installation plate body 1. The current sequentially passes through the first double reverse resistance wire 2, the second double reverse resistance wire 2 and the third double reverse resistance wire 2, and the current flows out from the third double reverse resistance wire 2 on the back surface of the installation plate body 1. The resistance value of series connection is three times the resistance value of a single double reverse resistance wire 2.

[0046] The application further provides a dry capacitor 10 detection system, comprising the non-inductive resistance device 9, and further comprising a high-voltage power supply 11, the dry capacitor 10, the inductive coil 8, the first electrode 12, the second electrode 16, a movable double electrode and a controller, wherein the controller is in communication connection with the movable double electrode, the movable double electrode comprises a double-head cylinder 14, and the first movable electrode 13 and the second movable electrode 15 are respectively arranged on the extending end of the double-head cylinder 14, the first movable electrode 13 and the first electrode 12 are arranged correspondingly, and the second movable electrode 15 and the second electrode 16 are arranged correspondingly, the inductive amount of the loop inductance generated by the inductive coil 8 is 0-60 μH, and the peak value of the discharge current of the dry capacitor 10 ranges from 0 to 5 kA. It should be noted that the first electrode 12, the second electrode 16 and the movable double electrode are mounted on the same mounting seat, and the extending end and the movable electrode are insulated.

[0047] The dry capacitor 10 detection system comprises two states, i.e. a charging state and a discharging state of the dry capacitor 10. When the dry capacitor 10 is in the charging state, as shown in FIG. 2, the movable double electrode controls the first electrode 12 to be separated from the first movable electrode 13 and the second electrode 16 to be connected with the second movable electrode 15, at this time, the positive pole of the high-voltage power supply 11 is connected with the high-voltage end electrode of the dry capacitor 10, the negative pole of the high-voltage power supply 11 is connected with the second electrode 16, the low-voltage end electrode of the dry capacitor 10 is used for connecting the second movable electrode 15, the second electrode 16 is connected with the second movable electrode 15, the current flowing out of the positive pole of the high-voltage power supply 11 reaches the high-voltage end electrode of the dry capacitor 10, and the current flowing out of the negative pole of the high-voltage power supply 11 reaches the low-voltage end electrode of the dry capacitor 10 after passing through the second electrode 16 and the second movable electrode 15. Figure 5 When the dry capacitor 10 is in the discharging test state, the movable double electrode controls the first electrode 12 to be connected with the first movable electrode 13 and the second electrode 16 to be separated from the second movable electrode 15, at this time, the non-inductive resistance device 9, the inductive coil 8 and the first electrode 12 are sequentially connected with each other, the high-voltage end of the dry capacitor 10 is connected with the non-inductive resistance device 9, the low-voltage end electrode of the dry capacitor 10 is connected with the first movable electrode 13 of the movable double electrode, the first electrode 12 is connected with the first movable electrode 13, and the current flowing out of the high-voltage end electrode of the dry capacitor 10 reaches the low-voltage end electrode of the dry capacitor 10 after sequentially passing through the non-inductive resistance device 9, the inductive coil 8, the first electrode 12 and the first movable electrode 13, so as to realize the discharging state of the dry capacitor 10. It should be noted that when the loop inductance, the charging voltage and the capacitance of the dry capacitor 10 are certain, the peak value of the discharge current can be regulated according to the resistance value of the non-inductive resistance device, so as to meet the current size specified in the test by regulating the resistance value of the non-inductive resistance device, and the peak value of the discharge current is regulated in the range shown in the following table:

[0048]

[0049] A detection method of a dry capacitor detection system, by detecting the discharge test state of the dry capacitor 10, in the test state, according to the test standard of the dry capacitor 10, the discharge current peak value is obtained, that is, the discharge current peak value is obtained according to the test standard, and the theoretical resistance value is obtained from the following formula:

[0050]

[0051]

[0052]

[0053] Wherein: I is the discharge current peak value, L is the loop inductance value, C is the capacitor capacitance value, R is the loop resistance value, and the resistance value of the non-inductive resistance device 9 is adjusted according to the theoretical resistance value, so as to carry out the short-circuit discharge test of the dry capacitor 10.

[0054] As an alternative embodiment, the number of double reverse resistance wires 2 can also be 2, 3, 4 or even more.

[0055] As an alternative embodiment, the opposite sides of the mounting plate body 1 are also provided with grooves suitable for accommodating the double reverse resistance wires 2.

[0056] As an alternative embodiment, the number of fixing plates 3 distributed on the opposite sides of the mounting plate body 1 can also be 2, 3 or even more.

[0057] As an alternative embodiment, the double reverse resistance wires 2 of the mounting plate body 1 can also be connected in parallel or series by 2, 4, 5 or even more.

[0058] As an alternative embodiment, the capacitance value of the dry capacitor 10, the inductance value of the inductor coil 8, the applied voltage value of the high-voltage power supply 11, and the double reverse resistance wires 2 can also be changed according to product specifications and experimental requirements.

[0059] Obviously, the above embodiments are only examples for clear illustration, and are not limited to the embodiments. Based on the above description, other different forms of changes or variations can also be made by those skilled in the art. Here, it is not necessary and impossible to enumerate all the embodiments. The obvious changes or variations derived therefrom are still within the protection scope of the present application.

Claims

1. A non-inductive resistance device, characterized by, The utility model relates to a non-inductive resistance device (9) and a test method thereof, and relates to the technical field of electrical equipment. It comprises: a mounting plate body (1); a double-strand reverse resistance wire (2) arranged on the mounting plate body (1) and adapted to be electrically connected with a dry capacitor (10), wherein the double-strand reverse resistance wire (2) obtains the current output by the dry capacitor (10) in a discharge state and is used for eliminating the self-induced inductance by using the current; the number of the double-strand reverse resistance wire (2) is at least two, and adjacent double-strand reverse resistance wires (2) are arranged on the mounting plate body (1) at equal intervals; the two ends of each double-strand reverse resistance wire (2) are fixed to mounting strips (4) on the two sides of the mounting plate body (1) through a fastening stud (7) respectively; an active connecting piece (6) is further arranged between two adjacent fastening studs (7), the active connecting piece (6) comprises two round holes for accommodating the fastening studs (7), and adjacent double-strand reverse resistance wires (2) are connected in parallel or in series through the active connecting piece (6) to form different resistance values; the mounting plate body (1) further comprises a fixing plate (3) for fixing the double-strand reverse resistance wire (2); 2. The non-inductive resistance device of claim 1, wherein, the length of the double-strand reverse resistance wire (2) is 500-1500 mm, the withstand voltage value is 500-1500 VDC, and the resistance value is 0.128-0.384 Ω.

3. A dry capacitor detection system characterized by, The double-strand reverse resistance wire (2) has a "U" shape structure arranged on the opposite sides of the mounting plate body (1) respectively.

4. The dry capacitor testing system of claim 3, wherein, The utility model relates to a non-inductive resistance device (9) and a test method thereof, and relates to the technical field of electrical equipment.

5. A dry capacitor inspection method for use with the dry capacitor inspection system of claim 3, characterized by, It further comprises an inductance coil (8), a first electrode (12) and an active double electrode, the non-inductive resistance device (9), the inductance coil (8) and the first electrode (12) are sequentially connected with each other, the high-voltage electrode of the dry capacitor (10) is used for being connected with the non-inductive resistance device (9), the low-voltage electrode of the dry capacitor (10) is connected with the first active electrode (13) of the active double electrode, and the first electrode (12) and the first active electrode (13) are arranged correspondingly. It further comprises a second electrode (16) and a high-voltage power supply (11), the active double electrode comprises a second active electrode (15) and a double-head air cylinder (14), the two ends of the double-head air cylinder (14) are connected with the second active electrode (15) and the first active electrode (13) respectively, the positive electrode of the high-voltage power supply (11) is used for being electrically connected with the high-voltage electrode of the dry capacitor (10), the negative electrode of the high-voltage power supply (11) is connected with the second electrode (16), the low-voltage electrode of the dry capacitor (10) is used for being connected with the second active electrode (15), and the second electrode (16) and the second active electrode (15) are arranged correspondingly. In a test state, the peak discharge current of the dry capacitor (10) is obtained according to the test standard of the dry capacitor (10), and the theoretical resistance value is obtained according to the following formula: wherein I is the peak discharge current, L is the loop inductance value, C is the capacitor capacitance value, and R is the loop resistance value, and then the resistance value of the non-inductive resistance device (9) is adjusted according to the theoretical resistance value to perform a test.

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