How to measure temperature of transformer winding-INNO

Mengapakah belitan pengubah memerlukan pengukuran suhu

Suhu terpanas belitan pengubah adalah faktor penentu utama untuk selamat, economical operation, dan hayat perkhidmatan transformer. Penuaan yang disebabkan oleh terlalu panas struktur penebat pada titik paling panas penggulungan boleh berkembang menjadi kerosakan pada keseluruhan pengubah. Jadi pengeluar transformer dan jabatan operasi perlu segera memantau suhu tempat panas pengubah. Oleh itu, Piawaian IEEE C57.12.00-2000 memerlukan keupayaan untuk menentukan suhu dan lokasi titik panas.

Transformer kuasa adalah salah satu peralatan paling kritikal dalam rangkaian penghantaran kuasa, dan prestasi mereka adalah sangat penting untuk operasi yang boleh dipercayai bagi keseluruhan grid kuasa. Dalam pengubah kuasa, a portion of the electrical energy is converted into heat generated by the transformer. Although this heat is relatively small compared to the total energy converted by the entire transformer, it can cause a significant temperature rise in the transformer. This thermal effect not only leads to a decrease in the insulation capacity and lifespan of the transformer, but also is a limiting factor for the actual operation of the transformer. Oleh itu, studying the temperature field of transformers, especially the hot spot temperature, is of great significance. Seperti yang diketahui umum, the capacity of a transformer is directly proportional to its economic and technical indicators. Oleh itu, with the continuous progress of new processes and technologies, the voltage level and individual capacity of power transformers will continue to increase. As the single-phase capacity of transformers gradually increases, the thermal problems in transformers become increasingly urgent to be solved. The overheating of transformer windings not only causes accelerated aging of insulation and affects its service life, but also causes malignant accidents due to local overheating of windings both domestically and internationally. These accidents have caused huge economic losses to industrial production and have had a huge adverse impact on society. So the heating problem of transformers is increasingly attracting the close attention of transformer design and usage departments.

Fiber optic temperature measurement of transformer winding

The thermal design of large transformer windings has always been mainly to calculate the average temperature rise of the transformer winding to the oil. To obtain the hot spot temperature rise of the winding, empirical formulas can only be used to estimate it. With the increasing demand for safe operation of transformers from users, thermal design based on average coil temperature rise can no longer guarantee the reliability of transformers. Due to the aging caused by overheating of the local insulation structure in the hottest part of the winding, it is possible to develop into damage to the entire transformer. Oleh itu, the safety, economic operation, and service life of the transformer mainly depend on the hottest temperature of the transformer winding. Oleh itu, pemantauan tepat suhu titik panas belitan transformer telah menjadi jaminan untuk operasi transformer yang selamat dan menjimatkan. Kaedah pengukuran suhu tradisional untuk belitan pengubah kuasa termasuk pengukuran suhu rintangan haba, thermocouple temperature measurement, and infrared temperature measurement. Namun begitu, belitan terdedah kepada persekitaran yang keras seperti voltan tinggi, suhu tinggi, dan gangguan elektromagnet yang sangat kuat. Termistor dan termokopel menghantar isyarat melalui wayar logam dan terdedah kepada gangguan elektromagnet. Lebih-lebih lagi, wayar logam terdedah kepada minyak penebat untuk masa yang lama dan terdedah kepada litar pintas selepas penuaan. Termometer inframerah tidak boleh dipasang di dalam transformer. Pada masa ini, ia hanya boleh digunakan untuk mengukur permukaan tangki minyak dan permukaan luar transformer seperti sesendal, and the measurement results are affected by environmental temperature. Oleh itu, there is an urgent need for a new measurement method. Pada masa kini, countries around the world are generally shifting their focus to using fiber optic probes to directly measure the temperature of hotspots. Installing a fiber optic thermometer on a transformer does not significantly increase the overall production cost of the transformer, so foreign transformer manufacturers and operating departments widely adopt this technology.