The world's first UHV transformer low frequency heating power supply successfully developed

Recently, the State Grid Hubei Electric Power Research Institute combined ± 1100kV UHV field test technology innovative converter transformer low-frequency heating power supply for the first time in South Hami ± 800kV UHVDC converter transformer applications and achieved great success. The successful application of this technology completely solves the engineering problems caused by the fact that the winter low temperature causes the thermal oil of the converter transformer to take longer time to heat up and the low temperature start of the converter transformer. State Grid Hubei Electric Power Company Red Collar Power Research Institute team after nearly a year of tackling tough grams, the use of AC-AC frequency design of low frequency power 0.01 ~ 3Hz, the volume is the most advanced power frequency heating 1 / 20, weight 1/30, with a high degree of integration, security and stability, and can run for a long time. According to the pre-validated technical proposal, the research team carried out the heating test on a ± 800kV converter transformer with pole I of Hami South Converter Station using a low-frequency heating power supply under the joint witness of the manufacturer and well-known domestic experts in the industry. With the gradual decrease in frequency, the active current injected into the transformer gradually increased, weighing 405 tons of UHV transformer under the control of the experimenter, the oil temperature increased by 1 ℃ every 5 minutes ... ... The results show that the heating effect of the device is extremely remarkable, the heating time is only one-tenth of that of a large oil machine, and the main technical indexes of the converter in the heating process are measurable and controllable.