An on-load tap changer oil temperature monitoring integrated device for distribution transformer

Abstract

The utility model discloses a distribution transformer on -load voltage regulating switch oil temperature monitoring integration device, including control unit, sealing structure body, oil temperature monitoring module, remote monitoring interface, fixed unit, the sealing structure body is immersed in transformer oil, the sealing structure body is including transmission mechanism, contact system, vacuum arc extinguish chamber in, control unit receives control signal and controls transmission mechanism, transmission mechanism operation changes circuit contact in contact system and opens and closes, vacuum arc extinguish chamber is used for sealing structure body arc inside extinguishing, oil temperature monitoring module is fixedly connected through fixed unit the outside of sealing structure body, including remote monitoring interface connection between oil temperature monitoring module and control unit, and remote monitoring interface will oil temperature monitoring module's data, and pass to control unit. The utility model discloses through integration design, reduces installation and maintenance cost, improves the economy of equipment.

Description

Technical Field

[0001] This utility model relates to the field of power equipment monitoring, and in particular to an integrated device for monitoring the oil temperature of on-load tap changer of a distribution transformer. Background Technology

[0002] In existing technologies, on-load tap changers and oil temperature monitoring are typically treated as two independent systems. This design has the following significant drawbacks: High cost: The procurement, installation, and maintenance costs of two independent systems are high, increasing the overall investment in power equipment. Complex structure: Each system requires its own independent housing and wiring, resulting in a complex overall structure that is detrimental to the compactness and reliability of the equipment. Poor performance: Due to obstacles in data exchange and collaborative operation between the systems, inaccurate oil temperature monitoring or untimely tap changer response may occur, affecting the overall performance of the equipment. Cumbersome process: The installation and commissioning process of the two systems is cumbersome, increasing construction difficulty and time costs. Furthermore, existing oil temperature monitoring devices often lack precise sealing structures and temperature sensors, leading to frequent oil leaks and inaccurate monitoring data.

[0003] This application addresses the following shortcomings of the prior art:

[0004] (1) Low integration: Existing technology has failed to integrate oil temperature monitoring and on-load tap changer functions into a single unit, resulting in a large overall size of the equipment, which is not conducive to installation and maintenance.

[0005] (2) Low level of intelligence: The lack of remote monitoring interface and intelligent early warning system makes the operation management and fault early warning of equipment not timely and accurate. Utility Model Content

[0006] Purpose of the utility model: The present utility model aims to provide an integrated on-load tap changer oil temperature monitoring device, which improves the operational safety and stability of power equipment through highly integrated component design and optimized relative position layout.

[0007] Technical solution: An integrated device for monitoring the oil temperature of on-load tap changer in a distribution transformer, comprising a control unit, a sealed structure body, an oil temperature monitoring module, a remote monitoring interface, and a fixing unit;

[0008] The sealed structure body includes a tap selector, a transmission mechanism and a vacuum converter. After the moving contact of the tap selector selects the tap in the no-load state, the load current is switched to the selected tap through the vacuum converter. The vacuum converter includes a vacuum interrupter and a contact system. The vacuum interrupter is connected to the transformer oil chamber and uses the transformer oil as the insulating medium.

[0009] The transmission mechanism includes a stepper motor, a lead screw, and a gun mechanism. The control unit receives the secondary voltage sampling signal of the power system, drives the lead screw through the stepper motor of the transmission mechanism to compress and store energy in the energy storage spring of the gun mechanism, and releases the energy storage spring after the gear selector has pre-selected the gear, triggering the on / off action of the vacuum interrupter to achieve voltage regulation and arc extinguishing.

[0010] The oil temperature monitoring module is fixedly connected to the non-stressed area outside the sealed structure body through a fixing unit, and is connected to the control unit through a remote monitoring interface. The remote monitoring interface transmits the data of the oil temperature monitoring module to the control unit, and the control unit further uploads it to the remote monitoring system.

[0011] The oil temperature monitoring module includes an oil temperature sensor, a signal processing unit, and an early warning unit. The oil temperature sensor is a platinum resistance Pt100 sensor, which is directly immersed in the transformer oil. The temperature measurement range is -40℃ to 150℃, and the accuracy class is Class A (±0.15℃).

[0012] The signal processing unit includes a filtering circuit, an AD conversion module, and a nonlinear compensation module. The filtering circuit removes interference signals, the AD conversion module performs analog-to-digital conversion on the signal after removing interference signals, and the nonlinear compensation module performs nonlinear compensation on the digital signal.

[0013] The warning unit has a two-level alarm mode: the first-level alarm threshold is 70℃ (remote system push), and the second-level alarm threshold is 85℃. When the oil temperature exceeds 85℃ for 10 seconds, the control unit cuts off the on-load tap changer power supply and triggers forced cooling of the arc-extinguishing chamber.

[0014] The fixing unit includes a positioning plate, a fixing block, and an insert block. The positioning plate is fixed to the outside of the sealing structure body, and the fixing block is fixedly connected to the positioning plate by bolts. The fixing block is provided with a threaded mounting groove for installing the oil temperature monitoring module. The insert block is used to reinforce the installed oil temperature monitoring module.

[0015] The insert is a nut, and the surface of the nut is nitrided to prevent corrosion. The pitch tolerance between the inner thread of the mounting groove and the outer thread of the oil temperature monitoring module is ≤0.1mm.

[0016] The fixing block has a mounting groove in the non-stressed area, and the inside of the mounting groove is covered with a polytetrafluoroethylene insulating layer to avoid interference with the oil temperature sensor signal.

[0017] The bolt mechanism is a spring-energy-storage mechanism, including a helical energy-storage spring with adjustable compression and a release latch. The release latch is triggered and released by a lead screw driven by a stepper motor.

[0018] The timing control board within the control unit receives signals and regulates the on / off timing of the vacuum interrupter.

[0019] The sealed structure body is a horizontal vacuum on-load tap changer, which is horizontally mounted on the top of the transformer core, below the transformer tank cover, and shares an oil chamber with the transformer.

[0020] The horizontal vacuum on-load tap changer is directly connected to the transformer tank cover via a flange. The flange has an embedded sealing ring and forms a maintenance-free shared oil chamber with the transformer oil chamber.

[0021] The remote monitoring interface is an RS485 wired interface, and the communication protocol is compatible with the Modbus protocol.

[0022] The vacuum converter includes a permanent magnet vacuum switch and a transition resistor, and the permanent magnet vacuum switch switches a single resistor as the transition resistor.

[0023] The control unit adjusts the speed and rotation angle of the stepper motor according to the dynamic changes of the secondary voltage using a fuzzy PID algorithm, thereby achieving automated closed-loop control of the transformer output voltage.

[0024] Beneficial effects: (1) Reduced costs: Integrated design reduces procurement, installation and maintenance costs, improving the economy of the equipment. (2) Simplified structure: The compact cubic or cuboid shape efficiently integrates various functional modules into a single housing, simplifying the overall structure and improving the reliability and stability of the equipment. (3) Enhanced performance: Optimized data transmission and collaborative working mechanisms ensure accurate oil temperature monitoring and timely response of the pressure regulating switch, improving the overall performance of the equipment. (4) Optimized process: Simplified installation and commissioning processes reduce construction difficulty and time costs. Attached Figure Description

[0025] Figure 1 This is a structural schematic diagram of an embodiment of the present utility model;

[0026] Figure 2 This is a three-dimensional schematic diagram of an embodiment of the present utility model;

[0027] Figure 3 This is a schematic diagram of the sealing structure body according to an embodiment of the present utility model;

[0028] Figure 4 This is a schematic diagram of the fixed unit in an embodiment of the present utility model. Detailed Implementation

[0029] The technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments.

[0030] like Figure 1An integrated device for monitoring the oil temperature of an on-load tap changer in a distribution transformer includes a control unit 1, a sealed structure body 2, an oil temperature monitoring module 3, a remote monitoring interface 4, and a fixing unit 5; the sealed structure body 2 is immersed in transformer oil; the control unit receives control signals and controls the transmission mechanism.

[0031] The sealed structure body 2 is a horizontal vacuum on-load tap changer, including a range selector, a transmission mechanism 6 and a vacuum converter. After the moving contact of the range selector selects the tap in the no-load state, the load current is switched to the selected tap through the vacuum converter. The vacuum converter includes a vacuum interrupter 8 and a contact system 7. The vacuum interrupter 8 is connected to the transformer oil chamber and uses the transformer oil as the insulating medium.

[0032] The transmission mechanism 6 operates to change the connection and disconnection of the circuit contacts in the contact system 7. The transmission mechanism 6 includes a stepper motor, a lead screw, and a gun mechanism. The control unit 1 receives the secondary voltage sampling signal of the power system, drives the lead screw through the stepper motor of the transmission mechanism 6 to compress and store energy in the energy storage spring of the gun mechanism, and releases the energy storage spring after the gear selector has pre-selected the gear, triggering the on / off action of the vacuum interrupter 8 to achieve voltage regulation and arc extinguishing.

[0033] The oil temperature monitoring module 3 is fixedly connected to the non-stressed area outside the sealed structure body 2 through the fixing unit 5, and is connected to the control unit 1 through the remote monitoring interface 4. The remote monitoring interface 4 transmits the data of the oil temperature monitoring module 3 to the control unit 1, and the control unit 1 further uploads it to the remote monitoring system.

[0034] The oil temperature monitoring module 3 includes an oil temperature sensor, a signal processing unit, and an early warning unit. The oil temperature sensor is a platinum resistance Pt100 sensor, which is directly immersed in the transformer oil. The temperature measurement range is -40℃ to 150℃, and the accuracy class is A (±0.15℃).

[0035] The signal processing unit includes a filtering circuit, an AD conversion module, and a nonlinear compensation module. The filtering circuit removes interference signals, the AD conversion module performs analog-to-digital conversion on the signal after removing interference signals, and the nonlinear compensation module performs nonlinear compensation on the digital signal.

[0036] The warning unit has a two-level alarm mode. The first-level alarm threshold is 70℃ (remote system push), and the second-level alarm threshold is 85℃. When the oil temperature exceeds 85℃ for 10 seconds, the control unit 1 cuts off the on-load tap changer and triggers forced cooling of the arc-extinguishing chamber.

[0037] The fixing unit 5 includes a positioning plate 9, a fixing block 10, and an insert block 11. The positioning plate 9 is fixed on the outside of the sealing structure body 2, and the fixing block 10 is fixedly connected to the positioning plate 9 by bolts. The fixing block 10 is provided with a threaded mounting groove 12 for installing the oil temperature monitoring module 3. The insert block 11 is used to reinforce the installed oil temperature monitoring module 3.

[0038] The insert 11 is a nut, and the surface of the nut is nitrided to prevent corrosion. The pitch tolerance between the internal thread of the mounting groove 12 and the external thread of the oil temperature monitoring module 3 is ≤0.1mm.

[0039] The fixing block 10 has a mounting groove 12 in the non-stressed area. The inside of the mounting groove 12 is covered with a polytetrafluoroethylene insulating layer to avoid interference with the oil temperature sensor signal.

[0040] The bolt mechanism is a spring-energy-storage mechanism, including a helical energy-storage spring with adjustable compression and a release latch. The release latch is triggered and released by a lead screw driven by a stepper motor.

[0041] The timing control board in the control unit 1 receives signals and regulates the on / off timing of the vacuum interrupter 8.

[0042] The sealed structure body 2 is a horizontal vacuum on-load tap changer, which is horizontally mounted on the top of the transformer core, below the transformer tank cover, and shares an oil chamber with the transformer.

[0043] The horizontal vacuum on-load tap changer is directly connected to the transformer tank cover via a flange. The flange has an embedded sealing ring and forms a maintenance-free shared oil chamber with the transformer oil chamber.

[0044] The remote monitoring interface 4 is an RS485 wired interface, and the communication protocol is compatible with the Modbus protocol.

[0045] The vacuum converter includes a permanent magnet vacuum switch and a transition resistor, and the permanent magnet vacuum switch switches a single resistor as the transition resistor.

[0046] The control unit 1 adjusts the speed and rotation angle of the stepper motor according to the dynamic changes of the secondary side voltage through a fuzzy PID algorithm, thereby realizing the automated closed-loop control of the transformer output voltage.

[0047] The remote monitoring interface 4 connects to a remote monitoring system, which can display the equipment's operating status in real time and provide functions such as historical data query and trend analysis to help operators fully understand the equipment's operating condition. Simultaneously, by combining big data analytics and artificial intelligence technology, the remote monitoring system can intelligently identify abnormal situations, issue early warnings, and prevent potential failures.

Claims

1. An integrated device for monitoring the oil temperature of an on-load tap changer in a distribution transformer, characterized in that, Includes a control unit (1), a sealed structure body (2), an oil temperature monitoring module (3), a remote monitoring interface (4), and a fixing unit (5); The sealed structure body (2) includes a tap selector, a transmission mechanism (6) and a vacuum converter. After the moving contact of the tap selector selects the tap in the no-load state, the load current is switched to the selected tap through the vacuum converter. The vacuum converter includes a vacuum interrupter (8) and a contact system (7). The vacuum interrupter (8) is connected to the transformer oil chamber and uses transformer oil as the insulating medium. The transmission mechanism (6) includes a stepper motor, a lead screw and a gun mechanism. The control unit (1) receives the secondary voltage sampling signal of the power system, drives the lead screw through the stepper motor of the transmission mechanism (6), compresses the energy storage spring of the gun mechanism to store energy, and releases the energy storage spring after the gear selector has pre-selected the gear, triggering the on / off action of the vacuum interrupter (8) to achieve voltage regulation and arc extinguishing. The oil temperature monitoring module (3) is fixedly connected to the non-stressed area outside the sealed structure body (2) through the fixing unit (5), and is connected to the control unit (1) through the remote monitoring interface (4). The remote monitoring interface (4) transmits the data of the oil temperature monitoring module (3) to the control unit (1), and the control unit (1) uploads it to the remote monitoring system.

2. The integrated device for monitoring the oil temperature of an on-load tap changer in a distribution transformer according to claim 1, characterized in that, The oil temperature monitoring module (3) includes an oil temperature sensor, a signal processing unit, and an early warning unit; The signal processing unit includes a filtering circuit, an AD conversion module, and a nonlinear compensation module. The filtering circuit removes interference signals, the AD conversion module performs analog-to-digital conversion on the signal after removing interference signals, and the nonlinear compensation module performs nonlinear compensation on the digital signal. The early warning unit is a two-level alarm mode, with a first-level alarm threshold and a second-level alarm threshold. When the oil temperature exceeds the second-level alarm threshold for more than 10 seconds, the control unit (1) cuts off the on-load tap changer power supply and triggers the arc extinguishing chamber for forced cooling.

3. The integrated device for monitoring the oil temperature of an on-load tap changer in a distribution transformer according to claim 1, characterized in that, The fixing unit (5) includes a positioning plate (9), a fixing block (10) and an insert block (11). The positioning plate (9) is fixed on the outside of the sealing structure body (2). The fixing block (10) is fixedly connected to the positioning plate (9) by bolts. The fixing block (10) is provided with a threaded mounting groove (12) for installing the oil temperature monitoring module (3). The insert block (11) is used to reinforce the installed oil temperature monitoring module (3).

4. The integrated device for monitoring the oil temperature of an on-load tap changer in a distribution transformer according to claim 3, characterized in that, The insert (11) is a nut, and the surface of the nut is nitrided. The pitch tolerance between the internal thread of the mounting groove (12) and the external thread of the oil temperature monitoring module (3) is ≤0.1mm.

5. The integrated device for monitoring the oil temperature of an on-load tap changer in a distribution transformer according to claim 3, characterized in that, The fixing block (10) has an installation groove (12) in the non-stressed area, and the inside of the installation groove (12) is covered with a polytetrafluoroethylene insulation layer.

6. The integrated device for monitoring the oil temperature of an on-load tap changer in a distribution transformer according to claim 1, characterized in that, The bolt mechanism is a spring-energy-storage mechanism, including a helical energy-storage spring with adjustable compression and a release latch. The release latch is triggered and released by a lead screw driven by a stepper motor.

7. The integrated device for monitoring the oil temperature of an on-load tap changer in a distribution transformer according to claim 1, characterized in that, The timing control board in the control unit (1) receives signals and regulates the on / off timing of the vacuum interrupter (8).

8. The integrated device for monitoring the oil temperature of an on-load tap changer in a distribution transformer according to claim 1, characterized in that, The sealed structure body (2) is a horizontal vacuum on-load tap changer, which is horizontally mounted on the top of the transformer core, below the transformer tank cover, and shares the oil chamber with the transformer.

9. The integrated device for monitoring the oil temperature of an on-load tap changer in a distribution transformer according to claim 1, characterized in that, The remote monitoring interface (4) is an RS485 wired interface, and the communication protocol is compatible with the Modbus protocol.

10. The integrated device for monitoring the oil temperature of an on-load tap changer in a distribution transformer according to claim 1, characterized in that, The vacuum converter includes a permanent magnet vacuum switch and a transition resistor, and the permanent magnet vacuum switch switches a single resistor as the transition resistor.

Images