A circuit breaker online monitoring device

Abstract

The present invention discloses an online monitoring device for circuit breakers, which relates to the technical field of circuit breakers, and includes a collection host and a sensor electrically connected to the collection host. The collection host provides working power for the sensor, receives and processes the signal collected by the sensor, and the sensor includes an opening current sensor, a closing current sensor, an energy storage current sensor, and a non-contact linear stroke sensor. The non-contact linear stroke sensor collects the opening and closing stroke information of the circuit breaker and uploads it to the collection host. After the collection host analyzes the stroke information, it extracts the speed information, analyzes the time of just opening and just closing, and calculates the stroke parameters based on the time of just opening and just closing. The present invention adopts a non-contact linear stroke sensor to monitor the connecting rod connected to the moving contact, avoiding the problem of installing sensors on the moving and static contacts. The stroke sensing component and the stroke analysis component do not contact each other, and the sensing device is not affected by the movement trajectory of the connecting rod and will not be damaged.

Description

Technical Field

[0001] The present invention relates to the technical field of circuit breaker monitoring, and in particular to an online monitoring device for a circuit breaker. Background Art

[0002] The mechanical characteristic parameters such as opening distance, overtravel, speed, overshoot and rebound during the opening and closing process of the circuit breaker can directly reflect the movement characteristics and equipment status of the circuit breaker. Therefore, all circuit breakers will strictly control the above parameters during the design, production and testing process.

[0003] To obtain the above parameters, it is first necessary to accurately obtain the opening / closing time of the circuit breaker during the opening and closing process. However, conventional circuit breaker online monitoring equipment does not have the ability to obtain the opening / closing time parameters of the circuit breaker.

[0004] In order to monitor the mechanical characteristic parameters of the circuit breaker online, the existing practice is to pre-install sensors inside the circuit breaker before the circuit breaker leaves the factory. As described in patent document CN111781494A, this method uses a contact pressure sensor to identify the opening and closing action, and determines the opening and closing moment by the pressure change characteristics between the moving and static contacts at the opening and closing moment during the opening and closing process. This method is prone to cause wear and tear on the sensor probe after multiple opening and closing actions of the circuit breaker. At the same time, since the pressure sensor probe needs to be installed, the moving and static contacts need to be processed again, which causes the closing gap to change, affecting the normal use of the equipment; and this method can only install pressure sensors before the circuit breaker leaves the factory, which is not applicable to equipment that is already in operation and is not very practical.

[0005] Therefore, technicians in this field are committed to developing an online monitoring device for circuit breakers, which can obtain the opening and closing time of the circuit breaker in a non-invasive way without modifying the internal equipment of the circuit breaker, and then accurately calculate the travel parameters of the circuit breaker to realize online monitoring of the circuit breaker travel parameters. Summary of the invention

[0006] In view of the above-mentioned defects of the prior art, the technical problem to be solved by the present invention is to obtain the time when the circuit breaker is just opened and closed, and based on the time when the circuit breaker is just opened and closed, how to realize online monitoring of other travel parameters of the circuit breaker.

[0007] To achieve the above object, the present invention provides an online monitoring device for a circuit breaker, comprising: a collection host and a sensor electrically connected to the collection host, wherein the collection host provides a working power supply for the sensor, receives and processes the signal collected by the sensor; the sensor comprises an opening current sensor, a closing current sensor, an energy storage current sensor, and a non-contact linear travel sensor, wherein:

[0008] The opening current sensor is an open current sensor arranged on the power line of the opening circuit, which is used to monitor the power-on and power-off time of the opening circuit, collect the current change of the opening circuit during the opening action, and send the collected output voltage signal to the collection host for processing;

[0009] The closing current sensor is an open current sensor arranged on the power line of the closing circuit, which monitors the power-on and power-off moments of the closing circuit, collects the current change of the closing circuit during the closing action, and sends the collected output voltage signal to the collection host for processing;

[0010] The energy storage current sensor is an open-type current sensor arranged on the power line of the energy storage circuit. After judging that the closing circuit is energized, it starts continuous sampling of the energy storage circuit, monitors the current during the energy storage action, and sends the collected current signal to the collection host for processing;

[0011] The non-contact linear travel sensor collects the travel information of the circuit breaker opening and closing and uploads it to the collection host. After the collection host parses the travel information, it extracts the speed information, analyzes the time of just opening and just closing, and calculates the travel parameters based on the time of just opening and just closing.

[0012] Preferably, the non-contact linear travel sensor includes a U-shaped mounting plate 1, a concave clamping block 2, a convex clamping block 3, a bow-shaped clamping plate 4, a travel sensor 5, a travel resolver 6, and an L-shaped fixing plate 7. The left panel, right panel and front panel of the U-shaped mounting plate 1 are provided with connecting holes 10, and the left panel and the right panel are provided with mounting holes 9; a semicircular first concave hole 11 is provided in the middle of the concave clamping block 2, and first threaded holes 12 are provided on both sides; a semicircular second concave hole 13 with the same aperture as the first concave hole 11 is provided at the rear end of the convex clamping block 3, and second threaded holes 14 are provided on both sides, and the second threaded hole 14 matches the first threaded hole 12, and the convex clamping block 3 and the concave clamping block 2 are fixed on the circuit breaker connecting rod by screws through the first threaded hole 12 and the second threaded hole 14; the front end of the convex clamping block 3 is provided with a third threaded hole 15 and The bow-shaped clamp plate 4 is connected, and the stroke sensor 5 is fixed on the bow-shaped clamp plate 4; a groove 16 is provided in the middle of the stroke resolver 6, and the groove 16 matches the stroke sensor 5, and the stroke sensor 5 is located in the groove 16 after installation; the stroke resolver 6 is installed on a printed circuit board 17, and the printed circuit board 17 is provided with a fixing hole 18; the L-shaped fixing plate 7 is L-shaped, and is provided with a first waisted circular hole 19 in the horizontal direction and a second waisted circular hole 20 in the vertical direction. The L-shaped fixing plate 7 is installed on the U-shaped mounting plate 1 through the first waisted circular hole 19 in the horizontal direction; the second waisted circular hole 20 matches the fixing hole 18 of the printed circuit board 17, and the installation position of the stroke resolver 6 on the L-shaped fixing plate 7 is adjusted through the second waisted circular hole 20, so that the stroke sensor 5 is in the matching position of the groove 16.

[0013] Preferably, the diameter of the first recessed hole 11 is smaller than the diameter of the connecting rod.

[0014] Preferably, the printed circuit board 17 has a thickness of 1.6 mm.

[0015] Preferably, the mounting hole 9 is a pear-shaped hole.

[0016] Preferably, the travel sensor is in sheet shape.

[0017] Preferably, the distance between the stroke sensor 5 and the bottom of the groove 16 of the stroke resolver 6 in the horizontal direction is 0.5 mm;

[0018] Preferably, the stroke sensor 5 is located at a central position relative to the groove 16 of the stroke resolver 6 in the vertical direction.

[0019] Preferably, the number of the second round holes 20 is four.

[0020] The present invention also provides a circuit breaker, wherein the circuit breaker comprises the circuit breaker online monitoring device as described above.

[0021] Technical Effects

[0022] 1. Using non-contact linear stroke sensor, the stroke sensing component and the stroke analysis component do not contact each other, the sensing device is not affected by the movement trajectory of the connecting rod and will not be damaged;

[0023] 2. The present invention does not directly monitor the moving and static contacts, but monitors the transmission component connecting rod connected to the moving contact, thereby avoiding the problem of installing sensors on the moving and static contacts, and also avoiding the problem of pre-installing sensors before the circuit breaker leaves the factory.

[0024] The concept, specific structure and technical effects of the present invention will be further described below in conjunction with the accompanying drawings to fully understand the purpose, characteristics and effects of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 It is a block diagram of the circuit breaker online monitoring device of a preferred embodiment of the present invention;

[0026] Figure 2 It is a schematic diagram of the installation of a non-contact linear travel sensor according to a preferred embodiment of the present invention;

[0027] Figure 3 This is a schematic diagram of a U-shaped bracket structure of a preferred embodiment of the present invention;

[0028] Figure 4 It is a schematic diagram of the structure of a concave clamp block of a preferred embodiment of the present invention;

[0029] Figure 5 It is a schematic diagram of the structure of a convex clamp block of a preferred embodiment of the present invention;

[0030] Figure 6 It is a schematic diagram of the bow-shaped splint structure of a preferred embodiment of the present invention;

[0031] Figure 7 It is a schematic diagram of the structure of a travel parser of a preferred embodiment of the present invention;

[0032] Figure 8 It is a schematic diagram of the L-shaped fixing plate structure of a preferred embodiment of the present invention.

[0033] In the attached drawings, 1. U-shaped bracket; 2. concave clamping block; 3. convex clamping block; 4. bow-shaped clamping plate; 5. stroke sensor; 6. stroke analyzer; 7. L-shaped fixing plate; 8. connecting rod; 9. mounting hole; 10. connecting hole; 11. first concave hole; 12. first threaded hole; 13. second concave hole; 14. second threaded hole; 15. third threaded hole; 16. groove; 17. printed circuit board; 18. fixing hole; 19. first waist circular hole; 20. second waist circular hole. DETAILED DESCRIPTION

[0034] The following describes several preferred embodiments of the present invention with reference to the drawings in the specification, so that the technical content is clearer and easier to understand. The present invention can be embodied in many different forms of embodiments, and the protection scope of the present invention is not limited to the embodiments mentioned in the text.

[0035] In the drawings, components with the same structure are indicated by the same numerical reference numerals, and components with similar structures or functions are indicated by similar numerical reference numerals. The size and thickness of each component shown in the drawings are arbitrarily shown, and the present invention does not limit the size and thickness of each component. In order to make the illustration clearer, the thickness of the components is appropriately exaggerated in some places in the drawings.

[0036] According to the provisions of GB1984-2014 "High Voltage AC Circuit Breakers", the definition of opening time is: for a circuit breaker in the closed position, the time interval from the moment the opening release (opening coil) is energized to the moment when all the arc contacts of each pole are separated; the definition of closing time is: for a circuit breaker in the open position, the time interval from the moment the closing circuit (closing coil) is energized to the moment when the contacts of all poles are in contact.

[0037] From the above definition, it can be seen that the just-opening moment refers to the moment when the moving and static contacts break contact during the opening process; the just-closing moment refers to the moment when the moving contact contacts the static contact for the first time.

[0038] like Figure 1 As shown, in a preferred embodiment of the present invention, the circuit breaker online monitoring device includes a data acquisition host, an opening current sensor, a closing current sensor, an energy storage current sensor, and a non-contact linear travel sensor.

[0039] The opening current sensor is an open-type current sensor, which is clamped on the opening circuit power line and is used to monitor the power on and off time of the opening circuit (opening coil); when there is no opening action, there is no current in the opening circuit, and the output voltage of the opening current sensor is the reference voltage V0; when there is an opening action, there is current in the opening circuit, and the output voltage Vi of the opening current sensor increases (or decreases, when the direction of the opening circuit current is the same as the default monitoring current direction of the opening current sensor, the output voltage increases, otherwise it decreases); when the difference between the two exceeds the set threshold, it can be determined that the opening circuit is energized.

[0040] The other end of the opening current sensor is connected to the acquisition host, which provides working power for the opening current sensor. The opening current sensor sends the collected output voltage signal to the acquisition host for processing. After determining that the opening circuit is energized, the acquisition host starts continuous sampling of the opening circuit current. The sampling time is determined according to the longest duration of the opening action of the circuit breaker, usually 100 to 200 mS, preferably 120 mS. At the same time, the continuous sampling of the opening stroke is started synchronously, and the sampling time is the same as the opening current sampling time.

[0041] The closing current sensor uses a sensor of the same model or function as the opening current sensor, is clamped on the closing circuit (closing coil), and monitors the power-on and power-off moments of the closing circuit.

[0042] The other end of the closing current sensor is connected to the acquisition host, and the acquisition host provides the working power supply for the closing current sensor. The closing current sensor sends the collected output voltage signal to the acquisition host for processing. After judging that the closing circuit is energized, the acquisition host starts continuous sampling of the closing circuit current. The sampling time is usually 100 to 200 mS, preferably 120 mS. The sampling of the closing stroke is started synchronously, and the sampling time is the same as the closing current sampling time.

[0043] The opening current sensor and the closing current sensor are used to monitor the opening circuit (opening coil) and the closing circuit (closing coil) in real time to obtain the initial energization time of the opening / closing coil, and the speed parameters of the moving contact during the opening and closing actions are extracted based on the stroke data to obtain the opening and closing moments. The opening time and the closing time can be obtained by subtracting the initial energization time from the opening and closing moments.

[0044] When it is determined that the closing circuit is energized, continuous sampling of the energy storage circuit is started at the same time. The sampling time is set according to the time required for the circuit breaker energy storage action, which can be slightly longer than the maximum time required for the energy storage action, usually 1S to 2S, preferably 1S.

[0045] The energy storage current sensor is of the same model or function as the opening current sensor, and is clamped on the energy storage circuit of the circuit breaker to monitor the current during the energy storage action process.

[0046] like Figure 2 to Figure 8 As shown, the non-contact linear travel sensor includes: a U-shaped mounting plate 1, a concave clamping block 2, a convex clamping block 3, a bow-shaped clamping plate 4, a travel sensor 5, a travel resolver 6, and an L-shaped fixing plate 7. The left and right panels of the U-shaped mounting plate 1 are provided with mounting holes 9, and the positions of the mounting holes 9 are the same as the positions of the fixing screws of the circuit breaker. The U-shaped mounting plate 1 is fixed to the circuit breaker by using the fixing screws provided by the circuit breaker.

[0047] In a preferred embodiment of the present invention, the mounting hole 9 is preferably a pear-shaped hole. During installation, it is not necessary to remove the fixing screws of the circuit breaker. It is only necessary to loosen the screws, insert the U-shaped mounting plate 1 into the fixing screws through the pear-shaped hole, and then tighten the fixing screws to achieve the installation of the U-shaped mounting plate 1.

[0048] In another preferred embodiment of the present invention, the left side panel, the right side panel and the front panel of the U-shaped mounting plate 1 are all provided with four connecting holes 10, and the number of the connecting holes 10 can be adjusted according to actual use needs. The positions of the four connecting holes 10 coincide with the positions of the holes opened in the L-shaped fixing plate 7, and the stroke resolver 6 is fixed to any one of the three surfaces of the U-shaped mounting plate by screws, and is fixed to the front in this embodiment;

[0049] The reason for designing three mounting surfaces is that the circuit breaker may need to be installed with other sensors. Having three mounting surfaces can avoid conflicts with other sensor installation positions, and it is preferred to install them on the front side.

[0050] like Figure 4 As shown, a semicircular first concave hole 11 is opened in the middle of the concave clamping block 2, and the diameter of the first concave hole 11 is slightly smaller than the diameter of the connecting rod 8, and first threaded holes 12 are opened on both sides of the concave clamping block 2;

[0051] like Figure 5 As shown, a semicircular second concave hole 13 is opened at the rear end of the convex clamping block 3, and the diameter of the second concave hole 13 is the same as the diameter of the first concave hole 11; second threaded holes 14 are opened on both sides of the convex clamping block 3, and the position matches the first threaded holes 12 of the concave clamping block 2.

[0052] During installation, the convex clamp block 3 and the concave clamp block 2 are clamped on the connecting rod 8, and the convex clamp block 3 and the concave clamp block 2 are fixed on the connecting rod by screws through the first threaded hole 12 and the second threaded hole 14.

[0053] In a preferred embodiment of the present invention, the front end of the convex clamp block 3 is square and has a third threaded hole 15. The bow-shaped clamp plate 4 is provided with a threaded hole corresponding to the third threaded hole 15, and is connected to the convex clamp block 3 by screws and fixed to the convex clamp block 3; a through hole is provided below the bow-shaped clamp plate 4, and the travel sensor 5 is fixed to the bow-shaped clamp plate 4 by screws.

[0054] When the circuit breaker has an opening and closing action, the connecting rod 8 drives the convex clamp block 3 and the concave clamp block 2 to move together, the convex clamp block 3 drives the bow-shaped clamp plate 4 to move synchronously, and the bow-shaped clamp plate 4 drives the travel sensor 5 to move synchronously, and finally the travel sensor 5 and the connecting rod 8 move synchronously, realizing the monitoring of the opening and closing action stroke.

[0055] Instead of directly monitoring the moving and static contacts, the transmission components connected to the moving contacts, such as connecting rods and rotating spindles, are monitored. In this way, the problem of installing sensors on the moving and static contacts is avoided, and the problem of pre-installing sensors before the circuit breaker leaves the factory is also avoided.

[0056] In another preferred embodiment of the present invention, the stroke sensor 5 is in the form of a sheet, and a groove 16 is provided in the middle of the stroke resolver 6, which matches the stroke sensor 5 and is inserted into the groove 16 of the stroke resolver after installation; the stroke resolver 6 is installed on a printed circuit board 17, and the printed circuit board 17 is provided with a fixing hole 18, and the board thickness is preferably 1.6 mm.

[0057] The L-shaped fixing plate 7 is L-shaped, and is provided with four first waisted circular holes 19 in the horizontal direction and four second waisted circular holes 20 in the vertical direction. The L-shaped fixing plate 7 is installed on the U-shaped mounting plate 1 through the four first waisted circular holes 19 in the horizontal direction.

[0058] The second waisted hole 20 matches with the fixing hole 18 of the stroke resolver 6. The installation position of the stroke resolver 6 on the L-shaped fixing plate 7 is adjusted through the second waisted hole 20 to ensure that the stroke sensor 5 is located in the center of the groove 16 in the vertical direction relative to the stroke resolver 6 and is at a matching distance from the bottom of the groove 16 in the horizontal direction, preferably 0.5 mm.

[0059] During the opening and closing movement of the circuit breaker, the movement trajectory of the connecting rod 8 is not a straight line, but an arc. The conventional contact stroke sensor is directly installed on the connecting rod 8, and the equipment is easily damaged. By using a non-contact linear stroke sensor, the stroke sensor 5 and the stroke resolver 6 do not contact each other, and the sensing equipment is not affected by the movement trajectory of the connecting rod 8 and will not be damaged.

[0060] The non-contact stroke sensor is connected to the acquisition host, and the acquisition host provides a working power supply for the non-contact stroke sensor. The non-contact linear stroke sensor uploads the opening and closing action stroke information to the acquisition host through a data line. After the acquisition host analyzes the opening and closing action stroke information, it extracts the speed information, analyzes the opening and closing time, and calculates other stroke parameters based on the opening and closing time.

[0061] At the moment of just opening and closing, due to the separation and contact action of the moving and static contacts, the movement speed of the moving contact is bound to change significantly. In an embodiment of the present invention, the movement speed parameter is extracted from the stroke data monitored by the non-contact linear stroke sensor, and the speed value that matches the changing pattern and the characteristics of the just opening and closing action is found. The moment corresponding to the speed is the moment of just opening or just closing. With the just opening / just closing moment and the starting moment of the opening and closing action, combined with the stroke data, according to the definition, the core parameters of the circuit breaker such as the opening distance, overtravel, total stroke, opening and closing speed during the opening and closing process can be calculated.

[0062] The preferred specific embodiments of the present invention are described in detail above. It should be understood that ordinary technicians in the field can make many modifications and changes based on the concept of the present invention without creative work. Therefore, all technical solutions that can be obtained by technicians in the technical field based on the concept of the present invention through logical analysis, reasoning or limited experiments on the basis of the prior art should be within the scope of protection determined by the claims.

Claims

1. A circuit breaker online monitoring device, characterized in that: include: A collection host and a sensor electrically connected to the collection host, wherein the collection host provides a working power supply for the sensor, receives and processes the signal collected by the sensor; the sensor includes an opening current sensor, a closing current sensor, an energy storage current sensor, and a non-contact linear travel sensor, wherein: The opening current sensor is an open current sensor arranged on the power line of the opening circuit, which is used to monitor the power-on and power-off time of the opening circuit, collect the current change of the opening circuit during the opening action, and send the collected output voltage signal to the collection host for processing; The closing current sensor is an open current sensor arranged on the power line of the closing circuit, which monitors the power-on and power-off moments of the closing circuit, collects the current change of the closing circuit during the closing action, and sends the collected output voltage signal to the collection host for processing; The energy storage current sensor is an open-type current sensor arranged on the power line of the energy storage circuit. After judging that the closing circuit is energized, it starts continuous sampling of the energy storage circuit, monitors the current during the energy storage action, and sends the collected current signal to the collection host for processing; The non-contact linear travel sensor collects the travel information of the circuit breaker opening and closing and uploads it to the collection host. After the collection host analyzes the travel information, it extracts the speed information and analyzes the time of just opening and just closing. Based on the time of just opening and just closing, the travel parameter is calculated; The non-contact linear travel sensor comprises a U-shaped mounting plate (1), a concave clamping block (2), a convex clamping block (3), a bow-shaped clamping plate (4), a travel sensor (5), a travel resolver (6), and an L-shaped fixing plate (7). The left side panel, the right side panel and the front panel of the U-shaped mounting plate (1) are provided with connecting holes (10), and the left side panel and the right side panel are provided with mounting holes (9); the concave clamping block (2) is provided with a semicircular first concave hole (11) in the middle and first threaded holes (12) on both sides; the rear end of the convex clamping block (3) is provided with a threaded hole (12) connected to the concave clamping block (2). A semicircular second concave hole (13) having the same aperture as the first concave hole (11) is provided with second threaded holes (14) on both sides, the second threaded holes (14) matching the first threaded holes (12), the convex clamping block (3) and the concave clamping block (2) being fixed to the circuit breaker connecting rod by screws through the first threaded holes (12) and the second threaded holes (14); a third threaded hole (15) is provided at the front end of the convex clamping block (3) and connected to the bow-shaped clamping plate (4), the travel sensor (5) being fixed on the bow-shaped clamping plate (4); the travel resolver (6) is provided in the middle A groove (16) is provided, the groove (16) matches the stroke sensor (5), and the stroke sensor (5) is located in the groove (16) after installation; the stroke resolver (6) is installed on a printed circuit board (17), and the printed circuit board (17) is provided with a fixing hole (18); the L-shaped fixing plate (7) is L-shaped, and is provided with a first waisted circular hole (19) in the horizontal direction and a second waisted circular hole (20) in the vertical direction, and the L-shaped fixing plate (7) is installed on the U-shaped mounting plate (1) through the first waisted circular hole (19) in the horizontal direction The second waisted hole (20) matches the fixing hole (18) of the printed circuit board (17); the installation position of the stroke resolver (6) on the L-shaped fixing plate (7) is adjusted through the second waisted hole (20) so that the stroke sensor (5) is located at a matching position of the groove (16); the distance between the stroke sensor (5) and the bottom of the groove (16) of the stroke resolver (6) in the horizontal direction is 0.5 mm, and the stroke sensor (5) is located in the center relative to the groove (16) of the stroke resolver (6) in the vertical direction.

2. The circuit breaker online monitoring device according to claim 1, characterized in that: The diameter of the first recessed hole (11) is smaller than the diameter of the connecting rod.

3. The circuit breaker online monitoring device according to claim 1, characterized in that: The printed circuit board (17) has a thickness of 1.6 mm.

4. The circuit breaker online monitoring device according to claim 1, characterized in that: The mounting hole (9) is a pear-shaped hole.

5. The circuit breaker online monitoring device according to claim 1, characterized in that: The travel sensor (5) is in the form of a sheet.

6. The circuit breaker online monitoring device according to claim 1, characterized in that: The number of the second girdle holes (20) is four.

7. A circuit breaker, characterized in that: The circuit breaker comprises the circuit breaker online monitoring device according to any one of claims 1 to 6.

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