On-line monitoring alarm controller for IT grounding system of power transformer

Abstract

The utility model provides an on-line monitoring alarm controller for a power transformer IT grounding system, which belongs to the field of controllers and comprises a device shell and a detection system, the detection system forms a main loop by connecting an incoming line terminal, an internal monitoring transformer and an outgoing line terminal, the internal monitoring transformer is connected with a signal rectifier, and the signal rectifier is connected with a power supply. The signal rectifier is connected with a signal filter, the signal filter is connected with a voltage comparator, the voltage comparator is divided into two branches, one branch is connected with a primary electric leakage monitoring drive circuit, the primary electric leakage monitoring drive circuit is connected to a primary alarm relay, the primary alarm relay is connected to a primary alarm outgoing line terminal, and the other branch is connected with a secondary alarm outgoing line terminal. And the other path is connected with the secondary electric leakage monitoring drive circuit. One end of the internal monitoring transformer is connected with the neutral line of the power supply transformer, and the other end of the internal monitoring transformer is connected with the ground, so that a monitoring system is formed.

Description

Technical Field

[0001] The utility model relates to the field of controllers, in particular to an online monitoring alarm controller for an IT grounding system of a power transformer. Background Art

[0002] Grounding resistance (power frequency) is the sum of the damping effects of the electric energy current introduced into the earth and the diffusion of the grounding body under the action of external electric energy. Its size is related to the way the grounding current begins to spread and the resistivity of the soil. There are three main types of grounding protection. Protective grounding, anti-static grounding, and lightning protection grounding. Grounding protection is the main method to avoid harm to people when electrical leakage faults occur. At this stage, people's application concept of grounding remains at the point that the fault analysis is completed when the electrical grounding device has been grounded. The concept proposed in this application is that the neutral line of the power supply equipment (power transformer or generator) has different grounding methods, and the change value of the grounding resistance is different. The circuit of the neutral line of the power supply (generation) equipment uses the conductivity of the physical layer of the ground surface to absorb various physical energies in the power grid and nature that are not conducive to people. The surface layer is divided into the surface layer (vertical depth of about 0-25 cm). This layer is affected by the surface humidity and various factors, and the resistance value varies greatly; the shallow surface layer (vertical depth of about 25-150 cm) has a relatively stable humidity, a large resistance value, and the resistance change is also affected by the humidity of the surface; the deep surface layer (vertical depth of more than 150 cm). The humidity at this level is very high and the resistance value is relatively small. Among these three levels, the surface layer is affected by the natural environment (humidity, temperature, etc.) and the conductivity varies greatly, which directly affects the change of grounding resistance. Especially in rainy season weather, the main reason why the resistance value from the surface layer to the deep surface layer becomes very small. When the neutral line of the power supply (generation) equipment and the earth form a TN (TN-S or TN-C) system, since the neutral line of the power supply (generation) equipment and the earth are deeply connected through the grounding grid (deeper than 2.5 meters), the leakage path formed by the power supply line of the power supply (generation) equipment to the ground is vertically downward from the surface layer (the current takes the path with the smallest resistance value). For the convenience of description and analysis, we refer to the resistance of this current path as "grounding vertical resistance". When the neutral line of the power supply (generation) equipment and the earth form an IT grounding system, since the neutral line of the power supply (generation) equipment is not connected to the earth, the neutral line and the earth are in a high resistance state, the current passing through the monitoring system is also very small, and the monitoring point is also the surface layer. The current loop path of the neutral line is horizontal to the surface of the ground. We refer to this current path resistance as "grounding horizontal resistance". After establishing these two concepts, the grounding fault analysis of the neutral line of the power supply (generation) equipment is much easier to understand. The grounding system of conventional power supply (generation) is "TN-CS" grounding, "three-phase four-wire" power supply mode. The neutral line of the transformer is directly grounded. The ground under people's feet is always the neutral line of the power supply (generation) equipment, which is the main cause of electric shock accidents. The fault point of line leakage and the neutral line of the power supply (generation) equipment are in a "grounding vertical resistance" relationship. When the leakage point is in an environment with high humidity on the surface layer (waterlogging in rainy season), a large current will flow from the leakage fault point to the ground.

[0003] The neutral point of the power supply in the IT grounding system is not grounded or is grounded through an impedance (greater than 1000Ω), and the neutral line is not led out to the outside. It is usually called a "three-phase three-wire" ungrounded system. In the same environment mentioned above, the conductive resistance of the IT grounding system is the "grounding horizontal resistance". The distance from the leakage point to the neutral line of the power supply (generation) equipment is very long, and the path is all surface electricity. In addition, the high leakage monitoring equipment has a high leakage current, so the current in the leakage circuit will be very small.

[0004] If the three-phase line voltage of the power supply (generation) equipment is adjusted to 0.23kv, and the neutral line system of the power supply (generation) equipment is set according to the IT grounding method, the conventional electrical appliances with a rated voltage of 220v still meet the working conditions and will not be affected by the customer's use. However, its power supply system is changed to a safe anti-electric shock power supply system.

[0005] The TN-CS power supply grounding method for power transformers has the following defects:

[0006] First, it is easy to cause electric shock accidents;

[0007] Second, the TN-CS grounding method is adopted. The three-phase four-wire system is a mixed power supply method. Due to the uneven single-phase power load, it is easy to cause three-phase voltage imbalance. Especially when the "neutral line" of the local power supply is poorly connected or seriously disconnected, it is easy for single-phase user-side electrical appliances to burn out, resulting in local power outages.

[0008] Third, the neutral line current is uneven, a large amount of resources are in a waiting state, and metal resources are wasted. Utility Model Content

[0009] The utility model aims to provide an online monitoring alarm controller for an IT grounding system of a power transformer to solve the problems raised by the above-mentioned background technology.

[0010] To achieve the above-mentioned purpose, the utility model provides the following technical solutions: an online monitoring alarm controller for the IT grounding system of a power transformer, which is a supporting product of the "10kV three-phase dual low-voltage power transformer" product and other power supplies that are not directly grounded, including a device housing and a detection system. The detection system is connected by an incoming terminal, an internal monitoring transformer and an outgoing terminal to form a main circuit. The incoming terminal is connected to the neutral line of the external power transformer, and the outgoing terminal is connected to the earth. The internal monitoring transformer of the device is respectively connected to the incoming and outgoing terminals. The grounding signal enters the internal monitoring transformer from the incoming terminal, and then enters the outgoing terminal from the internal monitoring transformer to form the main circuit; the The internal monitoring transformer is connected to the signal rectifier, the signal rectifier is connected to the signal filter, the signal filter is connected to the voltage comparator, the voltage comparator is divided into two branches, one is connected to the primary leakage monitoring drive circuit, the primary leakage monitoring drive circuit is connected to the primary alarm relay, the primary alarm relay is connected to the first-level alarm output terminal, and then the single-phase leakage alarm is output from the first-level alarm output terminal; the other is connected to the secondary leakage monitoring drive circuit, the secondary leakage monitoring drive circuit is connected to the secondary alarm relay, the secondary alarm relay is connected to the second-level alarm output terminal, and then the two-phase leakage enhanced alarm and control are output from the second-level alarm output terminal.

[0011] The two ends of the two guide wheels are fixedly mounted on the two ends of the two guide wheels, and the other ends of the two guide wheels are slidably connected to the two ends of the two guide wheels, and the two ends of the two guide wheels are fixedly mounted on the two ends of the two guide wheels, and the other ends of the two guide wheels are slidably connected to the two ends of the two guide wheels through a telescopic rod and a side wall of the two guide wheels. A spring is sleeved on the surface of the telescopic rod, and a limit block is fixedly mounted on the two ends of the two guide wheels, and the surface of the other end of the limit block is slidably connected to the limit groove opened on the other side of the inner wall of the slide groove. Two positioning holes are opened in the middle of the two sides of the inner wall of the mounting seat, and the inner wall of the positioning hole is connected to the hole groove opened on the side of the mounting block through a positioning pin. A protective component, the protective component includes two groups of guide blocks installed on the inner walls of two movable grooves, the surfaces of the two groups of guide blocks are fixedly connected to one side of two protective shells, rubber strips are provided on the opposite sides of the two protective shells, and through holes are opened on the sides of the two protective shells, and the inner walls of the through holes are provided with insulating layers.

[0012] As a preferred solution of the utility model: a plurality of card connectors are provided on the surface of the mounting plate, and the surfaces of the plurality of card connectors are engaged with a plurality of card holes provided on one side of the device housing, and a sponge layer is provided on the other side of the mounting plate.

[0013] As a preferred solution of the utility model: two fixing blocks are fixedly installed at both ends of the mounting seat, mounting holes are opened on the surfaces of the two fixing blocks, and bolts are arranged on the inner walls of the mounting holes.

[0014] As a preferred solution of the utility model: through holes are opened on both sides of the two groups of guide blocks, and the inner walls of the through holes are interlaced and connected with the guide rods provided on the inner wall of the movable groove.

[0015] As a preferred solution of the utility model: connection holes are opened at the four corners of one side of the device shell, the inner walls of several connection holes are snap-connected with several connectors on one side of the limit frame, and the inner wall of the limit frame is snap-connected with the sides of the two protective shells.

[0016] As a preferred solution of the utility model: a monitoring transformer is provided on one side of the device shell surface, a voltage comparator is provided in the middle of the device shell surface, a primary alarm relay is provided at one end of the voltage comparator, and two sets of secondary alarm relays are provided at the other end of the voltage comparator.

[0017] Compared with the prior art, the beneficial effects of the utility model are:

[0018] 1. The basic principle of the utility model is that the power transformer adopts IT grounding method in the power supply line system to monitor the health status of the power supply equipment. When the power supply line of the power transformer leaks, it cooperates with the internal monitoring transformer to issue a leakage alarm message. When the other phase line is detected to be grounded, it cooperates with the voltage comparator to issue two sets of secondary alarm control information. The secondary information can execute enhanced alarm or directly cut off the power supply, thereby avoiding the power supply safety hazards of the power supply system to the greatest extent. The device itself does not need an external power supply. One end of the internal monitoring transformer is connected to the neutral line of the power supply equipment, and the other end is connected to the ground, thereby forming a monitoring system.

[0019] 2. The device housing of the utility model is initially positioned by moving a plurality of mounting blocks in a plurality of slide grooves, and a plurality of clamping joints on the device housing are engaged with a plurality of clamping holes on the mounting plate, and a plurality of mounting blocks drive a plurality of limit blocks on the sliders to move in a plurality of limit grooves, and cooperate with the inner wall of the slide groove to squeeze a plurality of telescopic rods and springs until a plurality of positioning pins are inserted into a plurality of positioning holes and hole grooves, thereby fixing the mounting blocks and the mounting seat, so as to facilitate the fixing and disassembly of the device housing; by moving two protective shells and driving two sets of guide blocks on two guide rods on the inner walls of the two moving grooves The surface moves, and two rubber strips are used to prevent the two from touching each other. When the two protective shells are in contact, several connectors are engaged with several connecting holes, so that the inner wall of the limit frame is engaged with the sides of the two protective shells, thereby limiting them. The health status of the power supply equipment is monitored through the structure inside the device shell. When leakage occurs, a primary leakage alarm message is issued in cooperation with the internal monitoring transformer. When it is detected that another phase line is grounded, two sets of secondary alarm control messages are issued in cooperation with the voltage comparator. The secondary information can execute an enhanced alarm or directly cut off the power supply, thereby avoiding power supply hazards of the power supply system to the greatest extent. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 It is a schematic diagram of the structure of the utility model;

[0021] Figure 2 It is a partial structural schematic diagram of the utility model;

[0022] Figure 3 It is one of the partial structural schematic diagrams of the utility model;

[0023] Figure 4 This is a schematic diagram of the structure of the connection assembly of the utility model;

[0024] Figure 5 This is a schematic diagram of the structure of the protection component of the utility model;

[0025] Figure 6 This is a connection diagram of the detection system of the present utility model.

[0026] In the figure: 1. device housing; 11. mounting block; 12. movable slot; 13. hole slot; 14. snap-in hole; 15. connecting hole; 16. limiting frame; 17. connecting head; 2. connecting assembly; 21. mounting plate; 22. slider; 23. mounting seat; 24. slide slot; 25. telescopic rod; 26. spring; 27. limiting block; 28. limiting slot; 29. ​​positioning hole; 210. positioning pin; 211. snap joint; 212. sponge layer; 213. fixing block; 214. mounting hole; 215. bolt; 3. protection assembly; 31. guide block; 32. protection shell; 33. rubber strip; 34. through hole; 35. through hole; 36. guide rod. 37. Incoming terminal; 38. Outgoing terminal; 39. Internal monitoring transformer; 40. Signal rectifier; 41. Signal filter; 42. Voltage comparator; 43. Primary leakage monitoring drive circuit; 44. Secondary leakage monitoring drive circuit; 45. Primary alarm relay; 46. First-level alarm outlet terminal; 47. Secondary alarm relay; 48. Secondary alarm outlet terminal. DETAILED DESCRIPTION

[0027] In order to make the purpose, technical solution and advantages of the implementation of the utility model clearer, the technical solution in the implementation of the utility model will be clearly and completely described below in conjunction with the drawings in the implementation of the utility model. Obviously, the described implementation is a part of the implementation of the utility model, not all of the implementations. Based on the implementation of the utility model, all other implementations obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.

[0028] The incoming terminal 37 and the outgoing terminal 38 monitor the neutral line of the power transformer and the grounding information of the earth in real time. Its function is to monitor whether there is a loop current in the power supply line of the power transformer during the operation of the power transformer. If there is no leakage in the power supply line to the ground, there will be no voltage on the two terminals, indicating that the power supply line is good and safe. When leakage occurs in any phase of the power supply line, a loop current will occur in the neutral line of the power transformer, forming a voltage at both ends of the terminal. When there is a voltage between the incoming terminal 37 and the outgoing terminal 38, it means that there is a leakage fault in the power supply line. The internal monitoring transformer 39 receives the fault information and converts the signal into an appropriate AC voltage. It enters the voltage comparator 42 through the signal rectifier 40 and the signal filter 41. At the same time, the signal rectifier 40 also provides operating power for the entire system. The fault signal is identified by the voltage comparator 42, and the level of the fault signal is analyzed to drive the primary leakage monitoring drive circuit 43, the secondary leakage monitoring drive circuit 44, and the two relays 45 and 47 to drive each other to complete the overall monitoring and signal execution work. The first-level alarm production terminal 46 and the second-level alarm output terminal 48 are the output terminals of the two-way execution signal, which drive the peripheral execution electrical appliances to realize the leakage monitoring, alarm and control functions of the power transformer.

[0029] See also Figure 1-Figure 6 An online monitoring alarm controller in an IT grounding system includes a device housing 1 and a detection system. The device housing 1 protects the outer packaging of the entire product. Figure 6, the detection system shown in the figure is connected by an incoming terminal 37, an internal monitoring transformer 39 and an outgoing terminal 38 to form a main circuit. The incoming terminal 37 and the outgoing terminal 38 pass through the internal monitoring transformer 39. The neutral line of the power transformer and the earth are connected to the internal monitoring transformer. The grounding signal enters the internal monitoring transformer 39 from the incoming terminal 37, and then enters the outgoing terminal 38 from the transformer 39 to form a main circuit; the internal monitoring transformer 39 is connected to a signal rectifier 40, the signal rectifier 40 is connected to a signal filter 41, the signal filter 41 is connected to a voltage comparator 42, and the signal voltage generated by the internal monitoring transformer 39 is connected to the signal rectifier 40 in series with the signal filter 41. A signal filter 41 and a voltage comparator 42. The voltage comparator 42 is divided into two branches. One branch is connected to a primary leakage monitoring drive circuit 43. The primary leakage monitoring drive circuit 43 is connected to a primary alarm relay 45. The primary alarm relay 45 is connected to a first-level alarm output terminal 46. Then, a single-phase leakage alarm is output from the first-level alarm output terminal 46. The other branch is connected to a secondary leakage monitoring drive circuit 44. The secondary leakage monitoring drive circuit 44 is connected to a secondary alarm relay 47. The secondary alarm relay 47 is connected to a second-level alarm output terminal 48. Then, a two-phase leakage enhanced alarm and control is output from the second-level alarm output terminal 48. The second-level alarm output terminal 48 is composed of two groups of secondary alarm relays (respectively provided with normally open and normally closed to facilitate different controls for customers), with a total of twelve parts. The connection path of the function box is as follows: Figure 6 Run in the direction of the arrow.

[0030] The detection system inside the device casing 1 monitors the health status of the power supply equipment. When leakage occurs, it cooperates with the internal monitoring transformer 39 to issue a leakage alarm message. When it is detected that another phase line is grounded, it cooperates with the voltage comparator 42 to issue two sets of secondary alarm control information. The secondary information can execute an enhanced alarm or directly cut off the power supply, thereby avoiding power supply hazards of the power supply system to the greatest extent. The device itself does not require an external power supply. One end of the internal monitoring transformer 39 is connected to the neutral line of the power supply equipment, and the other end is connected to the ground, thereby forming a monitoring system.

[0031] During the operation of the detection system, when a phase of the power supply line (for example, phase A) leaks to the ground, the power supply of this phase is conducted through the ground to the input terminal 37 of the device, and then forms a loop with the neutral line of the transformer through the built-in internal monitoring transformer 39 and the output terminal 38 of "the device", forming the power supply and signal voltage of "the device". The signal voltage enters the signal filter 41 through the signal rectifier 40, and then enters the voltage comparator 42. The voltage comparator 42 theoretically judges that the signal voltage is a single-phase voltage level based on the phase difference of the three-phase power supply of the power supply (generation) equipment of 120°, and the algebraic sum of the instantaneous values ​​of the three-phase symmetrical sinusoidal AC voltage is equal to 0. The voltage comparator 42 sends a driving signal to the primary leakage monitoring drive circuit 43, and the primary leakage monitoring drive circuit 43 then drives the primary alarm relay 45 to drive the external fault alarm device (including various alarm devices). Thereby realizing the alarm function when a single-phase to ground fault occurs in the power transformer. This primary to ground leakage monitoring alarm function is suitable for any phase to ground fault of the three-phase power supply.

[0032] In this fault environment, if the power supply line is not handled in time, it is inevitable that another phase line will have a ground fault (for example: after the A phase power supply has already had a ground fault, the B phase will have a ground fault again. At this time, the power supply is prone to electric shock risk to people). The fault signal voltage emitted by the internal monitoring transformer 39 is also based on the phase difference of 120° between the three-phase power supply of the power supply (generation) equipment, and the algebraic sum of the instantaneous values ​​of the three-phase symmetrical sinusoidal AC voltage is equal to 0. Theoretically, it is judged that the signal voltage is a fault information of both phases to the ground. At this time, the voltage comparator 42 maintains the drive of the primary alarm relay 45 while sending a drive signal to the secondary leakage monitoring drive circuit 44. The secondary leakage monitoring drive circuit 44 then drives the secondary alarm relay 47 to drive the external enhanced fault alarm and control device (including equipment with various alarm modes and control modes), thereby realizing the alarm and forced control functions when a two-phase ground fault occurs in the power transformer.

[0033] Several mounting blocks 11 are fixedly mounted on the side of the device housing 1, and the surfaces of the several mounting blocks 11 are mounted and connected to the electrical equipment through the connecting components 2. Two movable grooves 12 are opened on the side of the surface of the device housing 1, and the inner walls of the two movable grooves 12 are provided with protective components 3;

[0034] See also Figure 4, connecting component 2, the connecting component 2 includes a mounting plate 21 that is snap-connected to one side of several mounting blocks 11, two sliders 22 are fixedly installed at both ends of the mounting plate 21, and the other ends of the two sliders 22 are slidably connected to two slide grooves 24 provided on both sides of the inner wall of the mounting seat 23, one side of the two sliders 22 is fixedly connected to one side of the inner wall of the slide groove 24 through a telescopic rod 25, and a spring 26 is sleeved on the surface of the telescopic rod 25. Limiting blocks 27 are fixedly installed on the sides of the two sliders 22, and the surface of the other end of the limiting block 27 is slidably connected to the limiting groove 28 provided on the other side of the inner wall of the slide groove 24. Two positioning holes 29 are provided in the middle of both sides of the inner wall of the mounting seat 23, and the inner wall of the positioning hole 29 is snap-connected with the hole groove 13 provided on the side of the mounting block 11 through a positioning pin 210.

[0035] During specific use: a plurality of mounting blocks 11 are moved in a plurality of slide grooves 24, a plurality of clamping joints 211 on the device housing 1 are engaged with a plurality of clamping holes 14 on the mounting plate 21, thereby preliminarily positioning it, a plurality of mounting blocks 11 drive a plurality of limit blocks 27 on the sliders 22 to move in a plurality of limit grooves 28, and cooperate with the inner wall of the slide groove 24 to squeeze a plurality of telescopic rods 25 and springs 26, until a plurality of positioning pins 210 are inserted into a plurality of positioning holes 29 and the hole groove 13, thereby fixing the mounting blocks 11 and the mounting base 23, so as to facilitate the fixing and disassembly of the device housing 1.

[0036] See also Figure 5 , the protective component 3 includes two groups of guide blocks 31 installed on the inner walls of the two movable grooves 12, the surfaces of the two groups of guide blocks 31 are fixedly connected to one side of the two protective shells 32, and the opposite sides of the two protective shells 32 are provided with rubber strips 33, and the sides of the two protective shells 32 are opened with through holes 34, and the inner walls of the through holes 34 are provided with insulating layers.

[0037] During specific use: move the two protective shells 32 and drive the two sets of guide blocks 31 to move on the surfaces of the two guide rods 36 on the inner walls of the two movable grooves 12, and cooperate with the two rubber strips 33 to prevent the two from touching each other. When the two protective shells 32 are in contact, engage the several connecting heads 17 with the several connecting holes 15, so that the inner wall of the limit frame 16 engages with the sides of the two protective shells 32, thereby limiting them.

[0038] See also Figure 3 , Figure 4 A plurality of card connectors 211 are provided on the surface of the mounting plate 21 , and the surfaces of the plurality of card connectors 211 are engaged with a plurality of card holes 14 provided on one side of the device housing 1 , and a sponge layer 212 is provided on the other side of the mounting plate 21 .

[0039] During specific use: a plurality of card connectors 211 on the device housing 1 are engaged with a plurality of card holes 14 on the mounting plate 21 to initially position it, and cooperate with the sponge layer 212 on the other side of the mounting plate 21 to facilitate protection of its inner bottom.

[0040] See also Figure 4 Two fixing blocks 213 are fixedly mounted at both ends of the mounting seat 23 , and mounting holes 214 are provided on the surfaces of the two fixing blocks 213 , and bolts 215 are provided on the inner walls of the mounting holes 214 .

[0041] During specific use, the bolt 215 is inserted into the mounting hole 214 on the fixing block 213, so as to facilitate the mounting and fixing of the mounting base 23 to the surface of the equipment.

[0042] See also Figure 5 Through holes 35 are provided on both sides of the two sets of guide blocks 31 , and the inner walls of the through holes 35 are interlaced and connected with guide rods 36 provided on the inner wall of the moving groove 12 .

[0043] During specific use, the two groups of guide blocks 31 cooperate with the through holes 35 to facilitate movement on the surfaces of the two guide rods 36 .

[0044] See also Figure 2 Connection holes 15 are provided at the four corners of one side of the device housing 1 , and the inner walls of several connection holes 15 are snap-connected with several connectors 17 on one side of the limit frame 16 , and the inner wall of the limit frame 16 is snap-connected with the sides of the two protective shells 32 .

[0045] During specific use: when two protective shells 32 are in contact, a plurality of connectors 17 are engaged with a plurality of connecting holes 15 , so that the inner wall of the limiting frame 16 is engaged with the sides of the two protective shells 32 , thereby limiting them.

[0046] See also Figure 2 An internal monitoring transformer 39 is provided on one side of the surface of the device housing 1, a voltage comparator 42 is provided in the middle of the surface of the device housing 1, a primary alarm relay 45 is provided at one end of the voltage comparator 42, and two sets of secondary alarm relays 47 are provided at the other end of the voltage comparator 42.

[0047] When in use, the plurality of mounting blocks 11 are moved in the plurality of slide grooves 24, and the plurality of clamping joints 211 on the device housing 1 are engaged with the plurality of clamping holes 14 on the mounting plate 21, so as to initially position it, and the plurality of mounting blocks 11 drive the plurality of limiting blocks 27 on the sliders 22 to move in the plurality of limiting grooves 28, and cooperate with the inner wall of the slide groove 24 to squeeze the plurality of telescopic rods 25 and the spring 26, until the plurality of positioning pins 210 are inserted into the plurality of positioning holes 29 and the hole groove 13, The mounting block 11 is thereby fixedly installed with the mounting seat 23, so as to facilitate the fixing and disassembly of the device housing 1, and the two protective shells 32 are moved and drive the two groups of guide blocks 31 to move on the surfaces of the two guide rods 36 on the inner walls of the two movable grooves 12, and cooperate with the two rubber strips 33 to prevent the two from touching each other. When the two protective shells 32 are in contact, a plurality of connecting heads 17 are engaged with a plurality of connecting holes 15, so that the inner wall of the limit frame 16 is engaged with the sides of the two protective shells 32, thereby limiting them.

[0048] The contents not described in detail in this specification belong to the prior art known to professional and technical personnel in the field. Although the present invention has been described in detail with reference to the aforementioned embodiments, it is still possible for technical personnel in the field to modify the technical solutions described in the aforementioned embodiments, or to make equivalent substitutions for some of the technical features therein. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention shall be included in the protection scope of the present invention.

Claims

1. An online monitoring alarm controller for an IT grounding system of a power transformer, comprising a device housing (1) and a detection system, characterized in that: The detection system shown is composed of an input terminal (37), an internal monitoring transformer (39) and an output terminal (38) connected to form a main circuit, the internal monitoring transformer (39) is connected to a signal rectifier (40), the signal rectifier (40) is connected to a signal filter (41), the signal filter (41) is connected to a voltage comparator (42), the voltage comparator (42) is divided into two branches, one of which is connected to a primary leakage monitoring drive circuit (43), the primary leakage monitoring drive circuit (43) is connected to a primary alarm relay (45), the primary alarm relay (45) is connected to a first-level alarm output terminal (46), and the other is connected to a secondary leakage monitoring drive circuit (44), the secondary leakage monitoring drive circuit (44) is connected to a secondary alarm relay (47), and the secondary alarm relay (47) is connected to a second-level alarm output terminal (48).

2. According to claim 1, an online monitoring alarm controller for an IT grounding system of a power transformer, characterized in that: A plurality of mounting blocks (11) are fixedly mounted on the side of the device housing (1), and the surfaces of the plurality of mounting blocks (11) are mounted and connected to the electrical equipment via a connecting assembly (2). Two movable grooves (12) are provided on the side of the surface of the device housing (1), and the inner walls of the two movable grooves (12) are provided with a protective assembly (3); a connecting assembly (2), wherein the connecting assembly (2) comprises a mounting plate (21) which is snap-fitted and connected to one side of the plurality of mounting blocks (11), two sliders (22) are fixedly mounted on both ends of the mounting plate (21), and the other ends of the two sliders (22) are slidably connected to two slide grooves (24) provided on both sides of the inner wall of the mounting seat (23), and one side of the two sliders (22) is fixedly connected to one side of the inner wall of the slide groove (24) via a telescopic rod (25), and a spring (26) is sleeved on the surface of the telescopic rod (25). The sides of the slider (22) are fixedly installed with a limit block (27), the surface of the other end of the limit block (27) is slidably connected to the limit groove (28) provided on the other side of the inner wall of the slide groove (24), and two positioning holes (29) are provided in the middle of the two sides of the inner wall of the mounting seat (23), and the inner wall of the positioning hole (29) is snap-connected with the hole groove (13) provided on the side of the mounting block (11) through a positioning pin (210); a protective component (3), the protective component (3) comprises two groups of guide blocks (31) installed on the inner walls of the two movable grooves (12), the surfaces of the two groups of guide blocks (31) are fixedly connected to one side of the two protective shells (32), the opposite sides of the two protective shells (32) are provided with a rubber strip (33), the sides of the two protective shells (32) are provided with a through hole (34), and the inner wall of the through hole (34) is provided with an insulating layer.

3. The online monitoring alarm controller for the IT grounding system of a power transformer according to claim 2 is characterized in that: A plurality of clamping joints (211) are provided on the surface of the mounting plate (21), and the surfaces of the plurality of clamping joints (211) are clamped and connected with a plurality of clamping holes (14) provided on one side of the device housing (1), and a sponge layer (212) is provided on the other side of the mounting plate (21).

4. The online monitoring alarm controller for the IT grounding system of a power transformer according to claim 2 is characterized in that: Two fixing blocks (213) are fixedly mounted on both ends of the mounting seat (23); surfaces of the two fixing blocks (213) are provided with mounting holes (214); inner walls of the mounting holes (214) are provided with bolts (215).

5. The online monitoring alarm controller for the IT grounding system of a power transformer according to claim 2 is characterized in that: Through holes (35) are provided on both sides of the two groups of guide blocks (31), and the inner walls of the through holes (35) are interlaced and connected with guide rods (36) provided on the inner walls of the movable grooves (12).

6. The online monitoring alarm controller for the IT grounding system of a power transformer according to claim 1, characterized in that: Connecting holes (15) are provided at four corners on one side of the device housing (1); the inner walls of a plurality of the connecting holes (15) are snap-connected with a plurality of connectors (17) on one side of a limiting frame (16); and the inner wall of the limiting frame (16) is snap-connected with the sides of two protective shells (32).

7. The online monitoring alarm controller for IT grounding system of power transformer according to claim 1, characterized in that: An internal monitoring transformer (39) is provided on one side of the surface of the device housing (1), a voltage comparator (42) is provided in the middle of the surface of the device housing (1), a primary alarm relay (45) is provided at one end of the voltage comparator (42), and two sets of secondary alarm relays (47) are provided at the other end of the voltage comparator (42).

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