A device for monitoring non-electric quantities of a power transformer

Abstract

The utility model discloses a kind of distribution transformer non-electric quantity monitoring devices, including pressure relief valve, the pressure relief valve is located at the top of circular shell, and with the top of circular shell is threadedly connected, acquisition module, the acquisition module is located at the bottom of circular shell, and is clamped with the inside of circular shell by snap spring, transmission module, the transmission module is located at one side of circular shell, encapsulation module, the encapsulation module is located at the outside of transmission module, and encapsulation module is connected with circular shell, this distribution transformer non-electric quantity monitoring device passes through oil temperature sensor, oil level sensor, pressure sensor acquisition oil level, oil temperature, the real-time data of pressure, then by signal conditioning calculation CPU board these data are packed into a data frame, by bluetooth chip, bluetooth antenna, the data of GPRS antenna far transmission, realize the oil level, oil temperature, pressure of each distribution transformer are monitored and transmission in real time, improve the reliability of power supply, reduce or eliminate the occurrence of non-human power failure.

Description

Technical Field

[0001] This utility model belongs to the field of non-electrical quantity monitoring technology, and more specifically, it relates to a non-electrical quantity monitoring device for distribution transformers. Background Technology

[0002] Distribution transformers are among the most widely used and critical pieces of equipment in power systems, and their operational safety directly impacts the lives of residents and the development of industry and agriculture. However, in reality, many distribution transformers experience oil leaks for various reasons, leading to operation in an oil-deficient state. Once a transformer lacks oil, the following problems will occur, affecting its stable operation: reduced heat dissipation, accelerated insulation aging, and impaired arc-extinguishing performance.

[0003] Reduced heat dissipation and overload operation can both lead to excessively high oil temperatures, increasing transformer losses and potentially causing outages. Due to the large number of these transformers, power system maintenance personnel cannot monitor the operation of each transformer in real time. To improve power supply reliability and reduce or eliminate non-human-caused power outages, it is clearly essential to monitor the oil level and temperature of each transformer in real time and upload this data to the maintenance department. This allows maintenance engineers to understand the "health" status of all transformers under their jurisdiction at any time. Utility Model Content

[0004] To address the shortcomings of existing technologies, this utility model provides a non-electrical quantity monitoring device for distribution transformers, thereby solving the problems mentioned in the background section.

[0005] To achieve the above objectives, this utility model provides the following technical solution: a distribution transformer non-electrical quantity monitoring device, comprising:

[0006] A pressure relief valve is located at the top of a circular housing and is threadedly connected to the top of the circular housing. The pressure relief valve consists of a pressure relief valve housing, a pressure spring, an upper sealing ring, a pressure relief valve cover, an adjusting screw, a spring bracket, and an adjusting nut.

[0007] The acquisition module is located at the bottom of the circular housing and is snapped into the circular housing by a snap ring. The acquisition module consists of an oil temperature sensor, an oil level sensor, a pressure sensor, a signal conditioning and calculation CPU board, and a mounting support frame.

[0008] The transmission module is located on one side of the circular housing and consists of a PCB board, a power supply battery, and a Bluetooth module. An airtight plug is provided at the connection between the transmission module and the circular housing.

[0009] The packaging module is located outside the transmission module and is connected to the circular housing.

[0010] As a preferred embodiment, the system also includes a host unit, which consists of a TTL-485 level conversion module, a CPU chip, a Bluetooth chip, a Bluetooth antenna, a GPRS antenna, a GPRS module, and an AC-DC power supply module.

[0011] As a preferred embodiment, the TTL-485 level conversion module converts the TTL level signal emitted by the CPU chip into an RS-485 level signal, and the Bluetooth chip and Bluetooth antenna are both connected to the CPU chip signal.

[0012] As a preferred embodiment, the encapsulation module includes a cover plate and a waterproof sealing ring, both of which are connected to an opening on the side of the circular housing.

[0013] As a preferred embodiment, the pressure relief valve cover and the adjusting nut are connected by a fixing adjusting screw, the spring bracket supports the pressure spring, the pressure relief valve housing is connected to the circular housing by a thread, and the pressure relief valve cover is waterproof.

[0014] As a preferred embodiment, the oil temperature sensor, oil level sensor, pressure sensor, and signal conditioning calculation CPU board are all mounted on a mounting support frame, which has an airflow guide hole and a lower sealing ring on the mounting nut.

[0015] As a preferred embodiment, the signal conditioning calculation CPU board is connected to the PCB board via upper and lower connecting wires.

[0016] This utility model provides a non-electrical quantity monitoring device for distribution transformers, which has the following beneficial effects:

[0017] This distribution transformer non-electrical quantity monitoring device collects real-time data on oil level, oil temperature, and pressure using oil temperature sensors, oil level sensors, and pressure sensors. The signal conditioning and calculation CPU board then packages this data into a data frame, which is transmitted to the transmission module via upper and lower connecting wires. The Bluetooth module on the transmission module transmits this data to the host computer. The host computer, through the CPU chip, Bluetooth chip, Bluetooth antenna, and GPRS antenna, achieves real-time monitoring and transmission of oil level and oil temperature data for each distribution transformer, improving power supply reliability, reducing or eliminating non-human-caused power outages, and allowing maintenance engineers to understand the "health" status of all distribution transformers under their jurisdiction at any time through real-time monitoring and transmission. Attached Figure Description

[0018] Figure 1 This is a schematic diagram of the structure of the distribution transformer non-electrical quantity monitoring device of this utility model;

[0019] Figure 2 This is a schematic diagram of the main unit of the distribution transformer non-electrical quantity monitoring device of this utility model.

[0020] In the diagram: 1. Oil temperature sensor; 2. Oil level sensor; 3. Mounting nut; 4. Lower sealing ring; 5. Signal conditioning and calculation CPU board; 6. Circular housing; 7. Gas seal insert; 8. PCB board; 9. Pressure relief valve housing; 10. Pressure spring; 11. Upper sealing ring; 12. Pressure relief valve cover; 13. Adjusting screw; 14. Spring bracket; 15. Adjusting nut; 16. Cover plate; 17. Waterproof sealing ring; 18. Power supply battery; 19. Bluetooth module; 20. Upper connecting wire; 21. Lower connecting wire; 22. Pressure sensor; 23. Mounting support frame; 24. Airflow guide hole; 25. Snap ring; 26. TTL-485 level conversion module; 27. CPU chip; 28. Bluetooth chip; 29. ​​Bluetooth antenna; 30. GPRS antenna; 31. GPRS module; 32. AC-DC power supply module. Detailed Implementation

[0021] The embodiments of this utility model will be described in further detail below with reference to the accompanying drawings and examples. The following examples are for illustrative purposes only and should not be construed as limiting the scope of this utility model.

[0022] In the description of this utility model, unless otherwise stated, "a plurality of" means two or more; the terms "upper," "lower," "left," "right," "inner," "outer," "front end," "rear end," "head," "tail," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this utility model. In addition, the terms "first," "second," "third," etc., are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0023] In the description of this utility model, it should be noted that, unless otherwise explicitly specified and limited, the terms "connected" and "linked" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium. Those skilled in the art can understand the specific meaning of the above terms in this utility model based on the specific circumstances.

[0024] For examples, please refer to Figure 1-2This utility model provides a technical solution: a non-electrical quantity monitoring device for a distribution transformer, comprising: a pressure relief valve, which is located at the top of a circular housing 6 and is threadedly connected to the top of the circular housing 6. When there is an internal fault in the distribution transformer, the gas pressure generated inside will rise sharply. When this pressure exceeds a certain value, it will automatically open to protect the distribution transformer in the fault situation and minimize losses; a data acquisition module, which is located at the bottom of the circular housing 6 and is connected to the circular housing 6 via a retaining ring 25; a transmission module, which is located on one side of the circular housing 6, and has an airtight plug 7 at the connection between the transmission module and the circular housing 6, which consists of a PCB board 8, a power supply battery 18, and a Bluetooth module 19. The Bluetooth module 19 and the Bluetooth antenna are connected by a wire, and the Bluetooth module 19 transmits the acquired data wirelessly to the Bluetooth antenna 29; and an encapsulation module, which is located outside the transmission module and is connected to the circular housing 6.

[0025] In this embodiment, a host computer is also included. The host computer consists of a TTL-485 level conversion module 26, a CPU chip 27, a Bluetooth chip 28, a Bluetooth antenna 29, a GPRS antenna 30, a GPRS module 31, and an AC-DC power supply module 32. The TTL-485 level conversion module 26 converts the TTL level signal sent by the CPU chip 27 into an RS-485 level signal to enable communication with external devices. It also converts the RS-485 signal sent by external devices into a TTL signal that the CPU chip 27 can recognize. The Bluetooth chip 28 and the Bluetooth antenna 29 are both connected to the CPU chip 27.

[0026] Specifically, the CPU chip 27 is used to organize the data sent from the Bluetooth chip 28 and Bluetooth antenna 29 into a data frame suitable for transmission uplink by the GPRS module 31, and send it out through the GPRS module 31 and GPRS antenna 30 (data uplink); similarly, it can also parse the data received from the GPRS antenna 30 and GPRS module 31 into a signal suitable for the Bluetooth chip 28 to accept, and send it out through the Bluetooth chip 28 and Bluetooth antenna 29 (data downlink).

[0027] In this embodiment, the encapsulation module includes a cover plate 16 and a waterproof sealing ring 17, both of which are connected to the opening on the side of the circular housing 6.

[0028] In this embodiment, the pressure relief valve consists of a pressure relief valve housing 9, a pressure spring 10, an upper sealing ring 11, a pressure relief valve cover 12, an adjusting screw 13, a spring bracket 14, and an adjusting nut 15. The pressure relief valve cover 12 and the adjusting nut 15 are connected by a fixed adjusting screw 13. The spring bracket 14 supports the pressure spring 10. The pressure relief valve housing 9 is connected to the circular housing 6 by a thread, and the pressure relief valve cover 12 is waterproof.

[0029] Specifically, the pressure relief value standard in this embodiment meets the requirements of "Test Standard for Pressure Relief Valve for Transformers, JB / T7069-1993". When the internal air pressure of the distribution transformer increases for some reason, the gas flows upward through the airflow guide hole 24 in the mounting support frame 23 into the cavity of the circular shell 6 and the pressure relief valve shell 9, and attempts to open the pressure relief valve cover 12. When the internal pressure exceeds the upper limit specified in "JB / T 7069-1993", the pressure relief valve cover 12 separates from the upper sealing ring 11, and the gas is discharged outward. When the internal pressure drops below the lower limit specified in "JB / T 7069-1993", the pressure relief valve cover 12 returns to its original position under the tension of the pressure spring 10. By simply unscrewing the pressure relief valve shell 9, transformer oil can be temporarily added to the transformer.

[0030] In this embodiment, the acquisition module consists of an oil temperature sensor 1, an oil level sensor 2, a pressure sensor 22, a signal conditioning and calculation CPU board 5, and a mounting support frame 23. The oil temperature sensor 1, oil level sensor 2, pressure sensor 22, and signal conditioning and calculation CPU board 5 are all mounted on the mounting support frame 23. The signal conditioning and calculation CPU board 5 is connected to the PCB board 8 through an upper connecting wire 20 and a lower connecting wire 21. The signal conditioning and calculation CPU board 5 is a computer board used for conditioning, acquiring, and calculating oil temperature, oil level, and internal pressure of the distribution transformer. An airflow guide hole 24 is provided on the mounting support frame 23. The acquisition module is snapped into the circular housing 6 through a snap ring 25. A lower sealing ring 4 is provided on the mounting nut 3.

[0031] Specifically, the oil level is measured using the capacitance method, and the measurement principle is as follows:

[0032]

[0033] In the formula, C is the capacitance value, ε is the dielectric constant of the medium between the capacitor plates, and ε = ε0. εr. Where ε0 is the dielectric constant of vacuum, εr is the relative dielectric constant of the medium between the plates, A is the area covered by the two plates of the capacitor, and d is the distance between the two plates of the capacitor;

[0034] Since the medium is transformer oil, its constant ε is constant, and the distance d between the inner core and outer shell of the oil level sensor 2 is also fixed. Once ε and d are determined in the formula, the capacitance is directly proportional to A. When the oil level changes, the area filled with the medium between the capacitor plates changes, meaning the capacitance C changes. This capacitance value is conditioned, acquired, and calculated by the signal conditioning and calculation CPU board 5 mounted on the mounting support 23, and converted into the current oil level data.

[0035] This method of measuring liquid level using changes in capacitance can achieve an accuracy of ±1mm and has no "blind zone," which can fully meet the requirements for oil level measurement in distribution transformers.

[0036] Specifically, a wide-range digital oil temperature sensor 1 is embedded inside the core of the oil level sensor 2. This sensor reaches the bottom of the core of the oil level sensor 2 and is insulated from the core. Therefore, the measured value is the actual upper oil temperature of the distribution transformer. The measured value of the oil temperature sensor 1 is sent to the signal conditioning and calculation CPU board 5 through the built-in wire.

[0037] During normal operation, copper and iron losses cause the transformer oil temperature to rise, and a small amount of gas is also generated. Since the transformer is a closed cavity, the internal pressure will inevitably increase.

[0038] In this embodiment, the pressure sensor 22 is directly installed on the signal conditioning and computing CPU board 5, and the real-time internal pressure data is directly transmitted to the signal conditioning and computing CPU board 5.

[0039] The real-time data of oil level, oil temperature, and pressure mentioned above are directly interfaced with the signal conditioning and computing CPU board 5. The CPU in the signal conditioning and computing CPU board 5 packages this data into a data frame and sends it to the PCB board 8 through the lower connecting wire 21, the airtight connector 7, and the upper connecting wire 20. The CPU in the PCB board 8 immediately measures the voltage value of its own power supply battery 18 and packages these measured power supply battery voltage, oil temperature, oil level, and pressure data into a format recognized by the Bluetooth module 19, and transmits it outward through the Bluetooth antenna.

[0040] In the main unit of the distribution transformer non-electrical quantity monitoring device in this embodiment, a Bluetooth antenna 29 and a Bluetooth chip 28 with the same frequency as the Bluetooth module 19 are installed. After the CPU chip 27 receives the data sent from the Bluetooth chip 28, it immediately organizes the data frame into a frame recognized by the GPRS module 31 and sends it to the Internet of Things platform through the GPRS antenna 30 (data uplink).

[0041] Similarly, the data received from the IoT platform by the GPRS antenna 30 and GPRS module 31 directly enters the CPU chip 27. The CPU chip 27 converts the received data frame into a format recognized by the Bluetooth chip 28 and transmits it outward through the Bluetooth antenna 29.

[0042] The Bluetooth module 19, installed inside the circular housing 6, immediately transmits the received data to the PCB board 8. The CPU on the PCB board 8 immediately parses the meaning of this data frame and performs various necessary operations (data downlink).

[0043] In the main unit of the distribution transformer non-electrical quantity monitoring device in this embodiment, a TTL-485 level conversion module 26 is also designed to facilitate the local computer to perform various necessary parameter settings, debugging, and analysis of the distribution transformer non-electrical quantity monitoring device.

[0044] Below the tubular oil level, oil temperature, and pressure acquisition module, there is an installation nut 3 for the transformer interface. By removing the original analog tubular oil level gauge, the transformer non-electrical quantity monitoring device of this invention can be quickly installed, reducing the workload of installation.

[0045] The above description is only a preferred embodiment of the present utility model, but the protection scope of the present utility model is not limited thereto. Any equivalent substitutions or changes made by those skilled in the art within the technical scope disclosed in the present utility model, based on the technical solution and the inventive concept of the present utility model, should be included within the protection scope of the present utility model.

[0046] It will be apparent to those skilled in the art that this invention is not limited to the details of the exemplary embodiments described above, and that it can be implemented in other specific forms without departing from the spirit or essential characteristics of this invention. Therefore, the embodiments should be considered illustrative and non-limiting in all respects, and the scope of this invention is defined by the appended claims rather than the foregoing description. Thus, it is intended that all variations falling within the meaning and scope of equivalents of the claims be included within this invention. No reference numerals in the claims should be construed as limiting the scope of the claims.

Claims

1. A non-electrical quantity monitoring device for distribution transformers, characterized in that, include: The pressure relief valve is located at the top of the circular housing (6) and is threadedly connected to the top of the circular housing (6). The pressure relief valve consists of a pressure relief valve housing (9), a pressure spring (10), an upper sealing ring (11), a pressure relief valve cover (12), an adjusting screw (13), a spring bracket (14), and an adjusting nut (15). The acquisition module is located at the bottom of the circular housing (6) and is internally connected to the circular housing (6) by a snap ring (25). The acquisition module consists of an oil temperature sensor (1), an oil level sensor (2), a pressure sensor (22), a signal conditioning and calculation CPU board (5), and a mounting support frame (23). The transmission module is located on one side of the circular housing (6) and consists of a PCB board (8), a power supply battery (18), and a Bluetooth module (19). An airtight plug (7) is provided at the connection between the transmission module and the circular housing (6). The encapsulation module is located outside the transmission module and is connected to the circular housing (6).

2. The distribution transformer non-electrical quantity monitoring device according to claim 1, characterized in that: It also includes a host, which consists of a TTL-485 level conversion module (26), a CPU chip (27), a Bluetooth chip (28), a Bluetooth antenna (29), a GPRS antenna (30), a GPRS module (31), and an AC-DC power supply module (32).

3. The distribution transformer non-electrical quantity monitoring device according to claim 2, characterized in that: The TTL-485 level conversion module (26) converts the TTL level signal emitted by the CPU chip (27) into an RS-485 level signal. The Bluetooth chip (28) and Bluetooth antenna (29) are both connected to the CPU chip (27) via signal connection.

4. The distribution transformer non-electrical quantity monitoring device according to claim 1, characterized in that: The encapsulation module includes a cover plate (16) and a waterproof sealing ring (17), both of which are connected to the opening on the side of the circular housing (6).

5. A distribution transformer non-electrical quantity monitoring device according to claim 1, characterized in that: The pressure relief valve cover (12) and the adjusting nut (15) are connected by a fixed adjusting screw (13), the spring bracket (14) supports the pressure spring (10), the pressure relief valve housing (9) is connected to the circular housing (6) by a thread, and the pressure relief valve cover (12) is waterproof.

6. The distribution transformer non-electrical quantity monitoring device according to claim 1, characterized in that: The oil temperature sensor (1), oil level sensor (2), pressure sensor (22) and signal conditioning calculation CPU board (5) are all mounted on the mounting support frame (23). The mounting support frame (23) has an airflow guide hole (24) and a lower sealing ring (4) on the mounting nut (3).

7. A distribution transformer non-electrical quantity monitoring device according to claim 1, characterized in that: The signal conditioning calculation CPU board (5) and PCB board (8) are connected by an upper connecting wire (20) and a lower connecting wire (21).

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