Nuclear power plant dc panel insulation alarm setting verification device

Abstract

The utility model discloses a nuclear power plant DC disc insulation alarm fixed value calibrating device, including casing, plug, first switch, second switch, current transformer, first adjustable resistance, second adjustable resistance, third adjustable resistance and fourth adjustable resistance, the plug is installed in the first side plate, and the plug is used for connecting with the positive and negative pole of DC bus, first switch is used for switching the positive and negative pole of DC bus connection or disconnection, and second switch is used for switching the positive pole or negative pole of DC bus conduction, current transformer is used for connecting with insulation detector, first adjustable resistance, second adjustable resistance, third adjustable resistance and fourth adjustable resistance are connected in proper order, and first adjustable resistance is connected with second switch, and fourth adjustable resistance is grounded and is arranged, can not need to prepare test wiring separately, can complete the test of insulation monitor fixed value calibration, effectively avoid the risk of misoperation, misoperation and live part, effectively reduce the risk of personal electric shock.

Description

Technical Field

[0001] This utility model relates to the field of nuclear power technology, and in particular to a device for verifying the insulation alarm setting value of a DC panel in a nuclear power plant. Background Technology

[0002] In nuclear power plants, DC switchboards are indispensable, as they supply power to important instrumentation and control equipment, electrical control circuits, DC motors, DCS and other equipment.

[0003] DC insulation monitoring devices installed in DC switchboards play a crucial role in DC systems. Operational experience has shown that grounding in DC systems not only causes relay protection devices to malfunction or fail to operate, but can also lead to malfunctions or failures to operate primary equipment controlled by DC, seriously jeopardizing the safe and stable operation of the power system. Therefore, it is essential to monitor the DC system's insulation to ground in real time and promptly eliminate faults when grounding occurs.

[0004] The DC insulation monitoring device, acting as the main unit, can collect and display the insulation information of two busbar sections (positive busbar / negative busbar) in real time, and can immediately issue an alarm if an abnormality occurs. The alarm settings for the two insulation sections can be set according to site requirements, such as 30KΩ for section I and 10KΩ for section II. During the operation of the DC distribution panel, it is often necessary to verify the insulation alarm settings to ensure proper alarm function. Therefore, the annual inspection of DC distribution panels places high demands on the verification of DC insulation monitoring devices. Typically, a test cable and a sliding rheostat are connected in series between the positive and negative terminals and the grounding busbar on the outgoing terminal side of a spare switch to verify the circuit positioning and alarm functions of the insulation monitoring device. This test method carries the risk of accidental contact and electric shock when verifying the insulation monitoring device in operation. Utility Model Content

[0005] The technical problem to be solved by this utility model is to provide a DC panel insulation alarm setting value verification device for nuclear power plants, so as to solve the problem of the risk of accidental contact and electric shock during the verification process of DC insulation monitoring devices in related technologies.

[0006] The technical solution adopted by this utility model to solve its technical problem is: to construct a nuclear power plant DC panel insulation alarm setting value verification device, including a shell, a plug, a first switch, a second switch, a current transformer, a first adjustable resistor, a second adjustable resistor, a third adjustable resistor and a fourth adjustable resistor;

[0007] The shell has a cylindrical structure and includes a bottom plate and a first side plate, a second side plate, a third side plate and a fourth side plate connected to the bottom plate. The first side plate, the second side plate, the third side plate and the fourth side plate are connected in sequence, and the first side plate and the third side plate are arranged in parallel and opposite to each other, and the second side plate and the fourth side plate are arranged in parallel and opposite to each other.

[0008] The plug is installed on the first side plate and is used to connect to the positive and negative terminals of the DC bus. The first switch is installed inside the housing and is used to switch the plug to connect to or disconnect the positive and negative terminals of the DC bus. The second switch is installed on the third side plate and is used to switch the DC bus to be on or off. The current transformer is sleeved on the cable between the first switch and the second switch and is used to connect to an insulation tester. The first adjustable resistor, the second adjustable resistor, the third adjustable resistor, and the fourth adjustable resistor are connected in series. The first adjustable resistor is connected to the second switch, and the fourth adjustable resistor is grounded. The range of the first adjustable resistor is 0-900KΩ, the range of the second adjustable resistor is 0-90KΩ, the range of the third adjustable resistor is 0-9KΩ, and the range of the fourth adjustable resistor is 0-900Ω.

[0009] In some embodiments, the fourth adjustable resistor is connected to the second side plate via a cable.

[0010] In some embodiments, the second side plate is provided with a screw hole, and a metal fastener is provided at the end of the cable away from the fourth adjustable resistor, the metal fastener being used to connect with the screw hole.

[0011] In some embodiments, the diameter of the screw hole is 12.5 mm, and the metal fastener includes a bolt with a specification of M12.

[0012] In some embodiments, the second switch includes a single-pole double-throw switch.

[0013] In some embodiments, the third side panel is provided with at least one handle.

[0014] In some embodiments, the outer sides of the second side plate and the fourth side plate are respectively provided with a first guide rail and a second guide rail.

[0015] In some embodiments, guide grooves are provided on the outer sides of the second side plate and the fourth side plate, respectively.

[0016] In some embodiments, the lower part of the base plate is provided with pulleys.

[0017] In some embodiments, the housing is a single-piece structure.

[0018] The following are the beneficial effects of implementing this utility model: The nuclear power plant DC panel insulation alarm setting value verification device can be connected to the DC bus by utilizing the space of the spare drawer of the DC distribution panel during operation. The insulation alarm setting value can be verified by operating the first switch, second switch and other components. The insulation monitoring instrument setting value verification test can be completed without preparing additional test wiring, effectively avoiding the risk of misoperation and accidental contact with live parts, and effectively reducing the risk of electric shock. Attached Figure Description

[0019] To more clearly illustrate the technical solution of this utility model, the present utility model will be further described below in conjunction with the accompanying drawings and embodiments. It should be understood that the following drawings only show some embodiments of this utility model and should not be considered as a limitation of the scope. For those skilled in the art, other related drawings can be obtained from these drawings without creative effort. In the drawings:

[0020] Figure 1 This is an electrical schematic diagram of the nuclear power plant DC panel insulation alarm setting value verification device in some embodiments of this utility model;

[0021] Figure 2 This is a schematic diagram of the structure of the nuclear power plant DC panel insulation alarm setting value verification device in some embodiments of this utility model. Detailed Implementation

[0022] To provide a clearer understanding of the technical features, objectives, and effects of this utility model, the specific embodiments of this utility model are now described in detail with reference to the accompanying drawings. In the following description, it should be understood that the orientations or positional relationships indicated by terms such as "front," "rear," "upper," "lower," "left," "right," "longitudinal," "horizontal," "vertical," "horizontal," "top," "bottom," "inner," "outer," "head," and "tail" are based on the orientations or positional relationships shown in the accompanying drawings, and are constructed and operated in a specific orientation. They are only for the convenience of describing this technical solution and do not indicate that the device or component referred to must have a specific orientation; therefore, they should not be construed as limitations on this utility model.

[0023] It should also be noted that, unless otherwise explicitly specified and limited, terms such as "installation," "connection," "joining," "fixing," and "setting" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; 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; they can refer to the internal communication of two components or the interaction between two components. When an component is referred to as being "on" or "below" another component, the component can be located "directly" or "indirectly" on the other component, or there may be one or more intermediary components. The terms "first," "second," "third," etc., are only for the convenience of describing this technical solution and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Therefore, features defined with "first," "second," "third," etc., may explicitly or implicitly include one or more of that feature. For those skilled in the art, the specific meaning of the above terms in this utility model can be understood according to the specific circumstances.

[0024] In the following description, specific details such as particular system structures and techniques are set forth for illustrative purposes and not for limitation, in order to provide a thorough understanding of the embodiments of the present invention. However, those skilled in the art will understand that the present invention can be implemented in other embodiments without these specific details. In other instances, detailed descriptions of well-known systems, apparatuses, circuits, and methods are omitted so as not to obscure the description of the present invention with unnecessary detail.

[0025] See Figure 1 and Figure 2 This utility model discloses a DC panel insulation alarm setting verification device for nuclear power plants, including a housing 10, a plug 20, a first switch 30, a second switch 40, a current transformer 50, a first adjustable resistor 60, a second adjustable resistor 70, a third adjustable resistor 80, and a fourth adjustable resistor 90.

[0026] The housing 10 has a cylindrical structure and includes a bottom plate 11 and a first side plate 12, a second side plate 13, a third side plate 14 and a fourth side plate 15 connected to the bottom plate 11. The first side plate 12, the second side plate 13, the third side plate 14 and the fourth side plate 15 are connected in sequence, and the first side plate 12 and the third side plate 14 are arranged in parallel opposite to each other, and the second side plate 13 and the fourth side plate 15 are arranged in parallel opposite to each other.

[0027] The plug 20 is installed on the first side plate 12 and is used to connect to the positive and negative terminals of the DC bus. The first switch 30 is installed inside the housing 10 and can be connected to the plug 20 via a cable. The first switch 30 is used to switch the plug 20 to connect to or disconnect the positive and negative terminals of the DC bus. The second switch 40 is installed on the third side plate 14 and can be connected to the first switch 30 via a cable. The second switch 40 is used to switch the DC bus to either connect to the positive or negative terminal.

[0028] The current transformer 50 is mounted on the cable between the first switch 30 and the second switch 40, and the current transformer 50 is used to connect to the insulation tester. The current transformer 50 is used to transmit the monitored current signal to the insulation tester to measure the specific value of the grounding resistance.

[0029] The first adjustable resistor 60, the second adjustable resistor 70, the third adjustable resistor 80, and the fourth adjustable resistor 90 are connected in series. The first adjustable resistor 60 is connected to the second switch 40, and the fourth adjustable resistor 90 is grounded. The range of the first adjustable resistor 60 is 0-900KΩ, the range of the second adjustable resistor 70 is 0-90KΩ, the range of the third adjustable resistor 80 is 0-9KΩ, and the range of the fourth adjustable resistor 90 is 0-900Ω. The first adjustable resistor 60, the second adjustable resistor 70, the third adjustable resistor 80, and the fourth adjustable resistor 90 form a resistance adjustment device.

[0030] The first adjustable resistor 60 has ten settings: 0KΩ, 100KΩ, 200KΩ, 300KΩ, 400KΩ, 500KΩ, 600KΩ, 700KΩ, 800KΩ, and 900KΩ, which can be adjusted as needed. The second adjustable resistor 70 has ten settings: 0KΩ, 10KΩ, 20KΩ, 30KΩ, 40KΩ, 50KΩ, 60KΩ, 70KΩ, 80KΩ, and 90KΩ, which can be adjusted as needed. The third adjustable resistor 80 has ten settings: 0KΩ, 1KΩ, 2KΩ, 3KΩ, 4KΩ, 5KΩ, 6KΩ, 7KΩ, 8KΩ, and 9KΩ, which can be adjusted as needed. The fourth adjustable resistor 90 has ten positions: 0Ω, 100Ω, 200Ω, 300Ω, 400Ω, 500Ω, 600Ω, 700Ω, 800Ω, and 900Ω, which can be adjusted as needed. Therefore, the resistance of the DC panel insulation alarm setting verification device in a nuclear power plant can be adjusted within the range of 0-999.9KΩ.

[0031] In some embodiments, the fourth adjustable resistor 90 is connected to the second side plate 13 via a cable.

[0032] In some embodiments, the second side plate 13 is provided with a screw hole, and a metal fastener is provided at the end of the cable away from the fourth adjustable resistor 90 for connection with the screw hole. The metal fastener may be made of copper or aluminum alloy. The second side plate 13 may be made of a metal material, such as copper, stainless steel, or aluminum alloy, without specific limitation.

[0033] In some embodiments, the diameter of the screw hole is 12.5 mm, and the metal fastener includes a bolt of M12 specification.

[0034] In some embodiments, the first switch 30 may be fixed on the base plate 11, and the first switch 30 may be a miniature circuit breaker of model NXB-63C25. Of course, the model and specifications of the first switch 30 can be selected and set according to actual needs, and no specific limitation is made here.

[0035] In some embodiments, the second switch 40 includes a single-pole double-throw switch. The second switch 40 can be a rotary switch. The model of the second switch 40 can be an LA38 rotary switch. Of course, the model and specifications of the second switch 40 can be selected and set according to actual needs, and are not specifically limited here. The DC bus positive and negative grounding can be changed by rotating the knob of the second switch 40 without adjusting the wiring.

[0036] In some embodiments, the third side plate 14 is provided with at least one handle 16 to facilitate staff to push and pull the nuclear power plant DC panel insulation alarm setting value verification device.

[0037] In some embodiments, the outer sides of the second side plate 13 and the fourth side plate 15 are respectively provided with a first guide rail and a second guide rail to connect with the sliding grooves on both sides of the spare drawer of the DC distribution panel. In other embodiments, the outer sides of the second side plate 13 and the fourth side plate 15 are respectively provided with guide grooves to connect with the guide rails on both sides of the spare drawer of the DC distribution panel. It is understood that the guide rails or guide grooves can be provided according to the structure of the spare drawer of the DC distribution panel, and no specific limitation is made here.

[0038] In some embodiments, the lower part of the base plate 11 is provided with pulleys to facilitate smoother pushing and pulling of the nuclear power plant DC panel insulation alarm setting value verification device.

[0039] In some embodiments, the housing 10 is an integral structure. Of course, the various components of the housing 10 can also be detachably connected by threads, which is not specifically limited here.

[0040] Combination Figure 1 As shown, the DC panel insulation alarm setting verification device in this nuclear power plant is applied as follows:

[0041] 1. When verifying the insulation alarm setting of the DC distribution panel, the resistance adjustment device should first be adjusted to the maximum resistance value, i.e., 999.9KΩ.

[0042] 2. Connect the nuclear power plant DC panel insulation alarm setting value verification device to the DC bus system, that is, connect the plug 20 to the positive and negative poles of the DC bus, and operate the first switch 30 to conduct the positive and negative poles of the DC bus.

[0043] 3. Switch the second switch 40 from the middle position to the left position, and ground the positive terminal of the DC bus through the resistor adjustment device.

[0044] 4. Slowly adjust the resistance until the DC insulation alarm is triggered. Record the resistance value at this point to see if it is within the acceptable range. If it is not acceptable, adjust the insulation tester and repeat the verification.

[0045] 5. Adjust the resistance value to the maximum and confirm that the DC insulation alarm disappears.

[0046] 6. Turn the second switch 40 to the right side and verify the negative pole insulation alarm setting value in the same way.

[0047] 7. After the experiment is completed, disconnect the first switch 30 and pull out the housing 10 so that the plug 20 is separated from the positive and negative poles of the DC bus. The nuclear power plant DC panel insulation alarm setting value verification device can be pulled out of the space of the spare drawer of the DC distribution panel, so that the nuclear power plant DC panel insulation alarm setting value verification device is isolated from the DC bus.

[0048] The insulation alarm setting verification device for the nuclear power plant DC switchboard can be connected to the DC busbar using the space of the spare drawer of the DC switchboard during operation. The insulation alarm setting can be verified by operating the first switch, second switch and other components. The insulation monitoring instrument setting verification test can be completed without preparing additional test wiring, effectively avoiding the risk of misoperation and accidental contact with live parts.

[0049] The DC panel insulation alarm setting verification device in this nuclear power plant effectively reduces the risk of electric shock to personnel and equipment tripping, effectively reduces the risk of human-caused failure, and can effectively improve work efficiency.

[0050] It is understood that the above embodiments only illustrate preferred embodiments of the present utility model, and their descriptions are relatively specific and detailed, but they should not be construed as limiting the scope of the present utility model patent. It should be noted that for those skilled in the art, the above technical features can be freely combined, and several modifications and improvements can be made without departing from the concept of the present utility model, all of which fall within the protection scope of the present utility model. Therefore, all equivalent transformations and modifications made within the scope of the claims of the present utility model should fall within the coverage of the claims of the present utility model.

Claims

1. A device for verifying insulation alarm settings on a DC control panel in a nuclear power plant, characterized in that, It includes a housing (10), a plug (20), a first switch (30), a second switch (40), a current transformer (50), a first adjustable resistor (60), a second adjustable resistor (70), a third adjustable resistor (80), and a fourth adjustable resistor (90); The housing (10) has a cylindrical structure. The housing (10) includes a bottom plate (11) and a first side plate (12), a second side plate (13), a third side plate (14) and a fourth side plate (15) connected to the bottom plate (11). The first side plate (12), the second side plate (13), the third side plate (14) and the fourth side plate (15) are connected in sequence. The first side plate (12) and the third side plate (14) are arranged in parallel opposite to each other, and the second side plate (13) and the fourth side plate (15) are arranged in parallel opposite to each other. The plug (20) is installed on the first side plate (12) and is used to connect to the positive and negative terminals of the DC bus; the first switch (30) is installed inside the housing (10) and is used to switch the plug (20) to connect to or disconnect the positive and negative terminals of the DC bus; the second switch (40) is installed on the third side plate (14) and is used to switch the positive or negative terminals of the DC bus to be connected; the current transformer (50) is sleeved on the cable between the first switch (30) and the second switch (40), and the current transformer... The device (50) is used to connect to the insulation tester; the first adjustable resistor (60), the second adjustable resistor (70), the third adjustable resistor (80) and the fourth adjustable resistor (90) are connected in series, the first adjustable resistor (60) is connected to the second switch (40), and the fourth adjustable resistor (90) is grounded. The range of the first adjustable resistor (60) is 0-900KΩ, the range of the second adjustable resistor (70) is 0-90KΩ, the range of the third adjustable resistor (80) is 0-9KΩ, and the range of the fourth adjustable resistor (90) is 0-900Ω.

2. The nuclear power plant DC panel insulation alarm setting value verification device according to claim 1, characterized in that, The fourth adjustable resistor (90) is connected to the second side plate (13) via a cable.

3. The nuclear power plant DC panel insulation alarm setting value verification device according to claim 2, characterized in that, The second side plate (13) is provided with a screw hole, and the end of the cable away from the fourth adjustable resistor (90) is provided with a metal fastener, which is used to connect with the screw hole.

4. The nuclear power plant DC panel insulation alarm setting value verification device according to claim 3, characterized in that, The diameter of the screw hole is 12.5 mm, and the metal fastener includes a bolt with a specification of M12.

5. The nuclear power plant DC panel insulation alarm setting value verification device according to claim 1, characterized in that, The second switch (40) includes a single-pole double-throw switch.

6. The nuclear power plant DC panel insulation alarm setting value verification device according to claim 1, characterized in that, The third side plate (14) is provided with at least one handle (16).

7. The nuclear power plant DC panel insulation alarm setting value verification device according to claim 1, characterized in that, The second side plate (13) and the fourth side plate (15) are respectively provided with a first guide rail and a second guide rail on their outer sides.

8. The nuclear power plant DC panel insulation alarm setting value verification device according to claim 1, characterized in that, The second side plate (13) and the fourth side plate (15) are respectively provided with guide grooves on their outer sides.

9. The nuclear power plant DC panel insulation alarm setting value verification device according to claim 1, characterized in that, The bottom of the base plate (11) is provided with pulleys.

10. The nuclear power plant DC panel insulation alarm setting value verification device according to claim 1, characterized in that, The shell (10) is an integral structure.

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