Monitoring and diagnosis system of power transformer
By installing high-precision sensors on the transformer and combining ground sensors, and using signal processing technologies such as differential amplifiers and comparators, the problems of inefficiency and high false alarm rate of traditional transformer monitoring methods are solved, and more accurate and reliable monitoring is achieved, which improves the operation safety of the transformer and the stability of the power system.
Patent Information
- Application Number
- CN202421568442.1
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-07-03
- Publication Date
- 2025-03-28
- Estimated Expiration
- 2034-07-03
AI Technical Summary
Traditional transformer monitoring methods are inefficient and cannot monitor the transformer operating status in real time. The false alarm rate is high, which affects the accuracy and reliability of monitoring.
A monitoring and diagnosis system for power transformers is designed, using high-precision vibration sensors and temperature sensors, combined with ground-mounted vibration sensors and ambient temperature sensors, and using signal processing technologies such as differential amplifiers and comparators to eliminate the impact of external vibration and ambient temperature on monitoring.
It improves the accuracy of monitoring and reduces the false alarm rate. Through the intuitively displayed alarm system, the abnormal status of the transformer is quickly identified and timely maintained, which improves the operation safety of the transformer and the stability of the power system.
Smart Images
Figure CN222689288U_ABST
Abstract
Description
Technical Field
[0001] The utility model relates to the technical field of power transformer monitoring systems, in particular to a monitoring and diagnosis system for a power transformer. Background Art
[0002] In the power system, the transformer is one of the key equipment, and its operating status directly affects the stability and safety of the power system. Traditional transformer monitoring methods mainly rely on manual inspections and regular maintenance, which is inefficient and cannot monitor the operating status of the transformer in real time. With the development of technology, although some sensor-based automatic monitoring systems have emerged, these systems often cannot effectively distinguish between the vibration and temperature changes generated by the transformer itself and the influence of external factors (such as ground vibrations or ambient temperature changes caused by heavy vehicles passing by), resulting in a high false alarm rate, affecting the accuracy and reliability of monitoring.
[0003] The above information disclosed in this Background section is only for enhancement of understanding of the background of the present disclosure and therefore it may contain information that does not constitute the prior art that is already known to one of ordinary skill in the art. Utility Model Content
[0004] The purpose of the utility model is to provide a monitoring and diagnostic system for a power transformer to solve the problems raised in the above background technology.
[0005] In order to achieve the above purpose, the utility model provides the following technical solutions:
[0006] A monitoring and diagnostic system for a power transformer, comprising:
[0007] A sensing module, wherein the sensing module comprises a vibration sensing unit and a temperature sensing unit, and the vibration sensing unit and the temperature sensing unit are both electrically connected to the signal processing module;
[0008] A signal processing module, wherein the signal processing module comprises a first subtractor and a second subtractor, wherein input ends of the first subtractor and the second subtractor are both electrically connected to the sensing module, and output ends of the first subtractor and the second subtractor are both electrically connected to the signal analysis module;
[0009] A signal analysis module, the signal analysis module comprising a first comparator, a second comparator, an A / D conversion module and an analysis unit, the first comparator and the second comparator are respectively arranged corresponding to the first subtractor and the second subtractor, the output ends of the first comparator and the second comparator are both electrically connected to the A / D conversion module, the output end of the A / D conversion module is electrically connected to the input end of the analysis unit, and the output end of the analysis unit is electrically connected to the alarm module;
[0010] An alarm module comprises a first alarm light and a second alarm light, wherein the first alarm light and the second alarm light have different colors.
[0011] Preferably, the vibration sensing unit includes a first vibration sensor and a second vibration sensor, and the temperature sensing unit includes a first temperature sensor and a second temperature sensor.
[0012] Preferably, the first vibration sensor and the first temperature sensor are both arranged on the transformer, and the second vibration sensor and the second temperature sensor are both arranged on the ground.
[0013] Preferably, the first vibration sensor is connected to the positive input terminal of the first subtractor, and the second vibration sensor is connected to the negative input terminal of the first subtractor; the first temperature sensor is connected to the positive input terminal of the second subtractor, and the second temperature sensor is connected to the negative input terminal of the second subtractor.
[0014] Preferably, the output end of the first subtractor is electrically connected to an input end of the first comparator, the other input end of the first comparator is electrically connected to a signal line of a preset first reference voltage, the output end of the second subtractor is electrically connected to an input end of the second comparator, and the other input end of the second comparator is electrically connected to a signal line of a preset second reference voltage.
[0015] Preferably, the analysis unit is an AND gate and an OR gate, the two input ends of the AND gate and the OR gate are electrically connected to the output ends of the first comparator and the second comparator respectively, the output end of the AND gate is electrically connected to the driving end of the first alarm light, and the output end of the OR gate is electrically connected to the driving end of the second alarm light.
[0016] Compared with the prior art, the beneficial effects of the utility model are:
[0017] The utility model effectively eliminates the influence of external vibration and ambient temperature on transformer monitoring by installing high-precision vibration sensors and temperature sensors on the transformer, combining them with ground-mounted vibration sensors and ambient temperature sensors, and utilizing signal processing technologies such as differential amplifiers and comparators. This design not only improves the accuracy of monitoring and reduces the false alarm rate, but also enables maintenance personnel to quickly identify abnormal conditions of the transformer and perform maintenance in a timely manner through an intuitively displayed alarm system, thereby improving the operational safety of the transformer and the stability of the power system. In addition, the implementation of this solution simplifies the monitoring process, reduces the need for manual inspections, and reduces maintenance costs, with significant economic and social benefits. BRIEF DESCRIPTION OF THE DRAWINGS
[0018] Figure 1 This is a schematic diagram of the circuit structure of the utility model. DETAILED DESCRIPTION
[0019] In order to make the purpose, technical solutions and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with specific embodiments.
[0020] It should be noted that, unless otherwise defined, the technical terms or scientific terms used in the present invention should be understood by people with ordinary skills in the field to which the present invention belongs. The words "first", "second" and similar words used in the present invention do not indicate any order, quantity or importance, but are only used to distinguish different components. "Include" or "comprise" and similar words mean that the elements or objects appearing before the word include the elements or objects listed after the word and their equivalents, without excluding other elements or objects. "Connect" or "connected" and similar words are not limited to physical or mechanical connections, but may include electrical connections, whether direct or indirect. "Up", "down", "left", "right" and the like are only used to indicate relative positional relationships. When the absolute position of the described object changes, the relative positional relationship may also change accordingly.
[0021] Example:
[0022] See also Figure 1 , the utility model provides a technical solution:
[0023] A monitoring and diagnosis system for a power transformer comprises: a sensing module, a signal processing module, a signal analysis module and an alarm module.
[0024] The sensing module includes a vibration sensing unit and a temperature sensing unit, both of which are electrically connected to the A / D conversion module, which uses the A / D conversion module of ADS1115 and is electrically connected to the signal processing module. The vibration sensing unit includes a first vibration sensor and a second vibration sensor, both of which use the vibration sensor of the HBM C10 series, which has high accuracy, good stability, and is easy to install. It does not require workers to have high professional knowledge, and reduces false detection and false alarm caused by installation errors. The temperature sensing unit includes a first temperature sensor and a second temperature sensor, both of which use the temperature sensor of the DS18B20 series. The first vibration sensor and the first temperature sensor are both set on the transformer, and the second vibration sensor and the second temperature sensor are both set on the ground.
[0025] In this step, by installing the first vibration sensor on the transformer, the vibration of the transformer can be monitored, the abnormal working condition of the transformer can be discovered in time, and the maintenance personnel can perform maintenance in time. The second vibration sensor is installed on the ground to reduce false alarms caused by certain special circumstances. This is because when a heavy vehicle passes near the transformer, the ground will also vibrate, and this vibration is not caused by the transformer itself, so it is easy to cause false alarms. By setting the second vibration sensor to detect the vibration of the ground alone, the first vibration sensor can be corrected, which can improve the detection accuracy and reduce false alarms. Similarly, the first temperature sensor is used to measure the temperature of the transformer surface, and the second temperature sensor is used to measure the ambient temperature. By obtaining these two sets of data, the temperature generated by the transformer can be obtained, so as to judge its working condition. If only the temperature of the transformer surface is detected, in winter, even if the heat generated by the transformer is very high, the surface temperature will not rise to a large value, and the situation in summer is just the opposite, so it is difficult to set a threshold for comparison. By setting the first temperature sensor and the second temperature sensor, the temperature generated by the transformer itself is obtained, which reduces the impact of the environment and facilitates the setting of a threshold for comparison.
[0026] The signal analysis module includes a first comparator, a second comparator, an A / D conversion module and an analysis unit. The first comparator and the second comparator are respectively arranged corresponding to the first subtractor and the second subtractor. The output ends of the first comparator and the second comparator are electrically connected to the A / D conversion module. The output end of the A / D conversion module is electrically connected to the input end of the analysis unit. The output end of the analysis unit is electrically connected to the alarm module.
[0027] The first vibration sensor is connected to the positive input terminal of the first subtractor, and the second vibration sensor is connected to the negative input terminal of the first subtractor; the first temperature sensor is connected to the positive input terminal of the second subtractor, and the second temperature sensor is connected to the negative input terminal of the second subtractor.
[0028] In this step, the first subtractor and the second subtractor are both composed of a high-precision differential amplifier of model INA128. The positive input terminal of the differential amplifier is connected in parallel with a grounded voltage-dividing resistor, and the output terminal is connected in parallel with a feedback resistor and connected to its own negative input terminal. This is the circuit of the subtractor. Since the circuit of the subtractor is a prior art, it will not be described in detail here. It can be understood that the vibration data and temperature data detected by the vibration sensing unit and the temperature sensing unit are transmitted in the form of voltage signals. The greater the vibration amplitude and the higher the temperature, the greater the corresponding voltage value. By using the first subtractor to subtract the signals of the first vibration sensor and the second vibration sensor, and using the second subtractor to subtract the signals of the first temperature sensor and the second temperature sensor, it is equivalent to eliminating the influence of external vibration and ambient temperature on the transformer, and can better detect the condition of the transformer itself.
[0029] The output end of the first subtractor is electrically connected to an input end of the first comparator, the other input end of the first comparator is electrically connected to a signal line of a preset first reference voltage, the output end of the second subtractor is electrically connected to an input end of the second comparator, and the other input end of the second comparator is electrically connected to a signal line of a preset second reference voltage.
[0030] In this step, the first comparator and the second comparator both use LM393 series dual voltage comparators to compare whether the two voltage signals at the output end of the first subtractor and the output end of the second subtractor exceed the preset first reference signal Vp1 and second reference signal Vp2, which is equivalent to judging whether the vibration amplitude and temperature of the transformer itself exceed the threshold value, and outputting them in the form of digital signals through the A / D conversion module. This method of judging by setting the threshold value is a prior art and will not be elaborated here.
[0031] The alarm module includes a first alarm light and a second alarm light, and the first alarm light and the second alarm light have different colors. The analysis unit is an AND gate and an OR gate, and the two input ends of the AND gate and the OR gate are electrically connected to the output ends of the first comparator and the second comparator respectively, the output end of the AND gate is electrically connected to the driving end of the first alarm light, and the output end of the OR gate is electrically connected to the driving end of the second alarm light.
[0032] In this step, the first alarm light uses a red alarm light, the second alarm light uses an orange alarm light, the AND gate uses the AND gate chip of the 74HC08 series, and the OR gate uses the OR gate chip of the 74LS32 series, both of which have low power consumption. When one of the vibration amplitude or temperature of the transformer itself exceeds the threshold, the corresponding first comparator or second comparator will output a high level through the A / D conversion module, and will also output a high level after passing through the OR gate, and will output a low level after passing through the AND gate, so the orange second alarm light can be driven, indicating that one of the indicators of the transformer is abnormal. When the vibration amplitude and temperature of the transformer itself exceed the threshold, the corresponding first comparator and second comparator will both output a high level through the A / D conversion module, and will also output a high level after passing through the OR gate, and will also output a high level after passing through the AND gate, so the red first alarm light and the orange second alarm light can be driven at the same time, indicating that both indicators of the transformer are abnormal, so that users can intuitively understand the working status of the transformer according to the color of the light. The alarm light can be driven by a triode or directly driven by a high level output by an AND gate or an OR gate. Both driving methods are existing technologies and will not be described in detail here.
[0033] In summary, the utility model effectively eliminates the influence of external vibration and ambient temperature on transformer monitoring by installing high-precision vibration sensors and temperature sensors on the transformer, combining ground-mounted vibration sensors and ambient temperature sensors, and utilizing signal processing technologies such as differential amplifiers and comparators. This design not only improves the accuracy of monitoring and reduces the false alarm rate, but also enables maintenance personnel to quickly identify abnormal conditions of the transformer and perform maintenance in a timely manner through an intuitively displayed alarm system, thereby improving the operational safety of the transformer and the stability of the power system. In addition, the implementation of this solution simplifies the monitoring process, reduces the need for manual inspections, and reduces maintenance costs, with significant economic and social benefits.
[0034] The technical features of the above-described embodiments may be arbitrarily combined. To make the description concise, not all possible combinations of the technical features in the above-described embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.
[0035] The above-mentioned embodiments only express several implementation methods of the utility model, and the description is relatively specific and detailed, but it cannot be understood as limiting the scope of the utility model patent. It should be pointed out that for ordinary technicians in this field, several modifications and improvements can be made without departing from the concept of the utility model, which all belong to the protection scope of the utility model. Therefore, the protection scope of the utility model patent shall be based on the attached claims.
Claims
1. A monitoring and diagnostic system for a power transformer, characterized in that: include: A sensor module, wherein the sensor module includes a vibration sensor unit and a temperature sensor unit, and the vibration sensor unit and the temperature sensor unit are both electrically connected to the signal processing module; A signal processing module, wherein the signal processing module comprises a first subtractor and a second subtractor, wherein input ends of the first subtractor and the second subtractor are both electrically connected to the sensing module, and output ends of the first subtractor and the second subtractor are both electrically connected to the signal analysis module; A signal analysis module, the signal analysis module comprising a first comparator, a second comparator, an A / D conversion module and an analysis unit, the first comparator and the second comparator are respectively arranged corresponding to the first subtractor and the second subtractor, the output ends of the first comparator and the second comparator are both electrically connected to the A / D conversion module, the output end of the A / D conversion module is electrically connected to the input end of the analysis unit, and the output end of the analysis unit is electrically connected to the alarm module; An alarm module comprises a first alarm light and a second alarm light, wherein the first alarm light and the second alarm light have different colors.
2. A monitoring and diagnostic system for a power transformer according to claim 1, characterized in that: The vibration sensing unit includes a first vibration sensor and a second vibration sensor, and the temperature sensing unit includes a first temperature sensor and a second temperature sensor.
3. A monitoring and diagnostic system for a power transformer according to claim 2, characterized in that: The first vibration sensor and the first temperature sensor are both arranged on the transformer, and the second vibration sensor and the second temperature sensor are both arranged on the ground.
4. A monitoring and diagnostic system for a power transformer according to claim 3, characterized in that: The first vibration sensor is connected to the positive input terminal of the first subtractor, and the second vibration sensor is connected to the negative input terminal of the first subtractor; the first temperature sensor is connected to the positive input terminal of the second subtractor, and the second temperature sensor is connected to the negative input terminal of the second subtractor.
5. A monitoring and diagnostic system for a power transformer according to claim 4, characterized in that: The output end of the first subtractor is electrically connected to an input end of the first comparator, and the other input end of the first comparator is electrically connected to a signal line of a preset first reference voltage. The output end of the second subtractor is electrically connected to an input end of the second comparator, and the other input end of the second comparator is electrically connected to a signal line of a preset second reference voltage.
6. A monitoring and diagnostic system for a power transformer according to claim 5, characterized in that: The analysis unit is an AND gate and an OR gate, the two input ends of the AND gate and the OR gate are electrically connected to the output ends of the first comparator and the second comparator respectively, the output end of the AND gate is electrically connected to the driving end of the first alarm light, and the output end of the OR gate is electrically connected to the driving end of the second alarm light.