The bus processing machine distribution transformer refueling is not scientific: first, transformer oil has several oil base, winding machine different types of oil base in principle can not be mixed, the new addition of transformer oil and the transformer box oil model may not be consistent; Second, there is no power failure when the distribution transformer is refueled, resulting in the mixing of cold and hot oil inside the transformer, and the circulating oil flow is accelerated, and the moisture at the bottom of the transformer is taken up and circulated to the high and low voltage coil so that the insulation falls and causes a breakdown and short circuit; Third, the transformer oil is unqualified. In order to reduce the line loss and improve the utilization rate of the equipment, the reactive power compensation device should be used when the distribution transformer capacity is more than 100 kVA. If the compensation is not properly equal to the total capacitive reactance and total inductive reactance on the running line, ferromagnetic resonance will be generated in the running line and equipment, causing over voltage and over current, and burning distribution transformers and other electrical equipment. Lightning overvoltage, distribution transformers must be installed in the high and low voltage side qualified arrester, to reduce the lightning overvoltage, ferromagnetic resonance overvoltage on the transformer high and low voltage coil or bushings. Secondary short circuit when the distribution transformer secondary short circuit in the secondary side is higher than the rated current several times or even more short circuit current, automatic winding machine and at the same time in the primary side also want to make a big electric current to offset the secondary side short-circuit current demagnetization effect, strong short circuit current, on the one hand, the transformer coil inside will have a huge mechanical stress, the coil compression. Main and auxiliary insulation loose off, coil deformation. On the other hand, due to the existence of short-circuit current, lead to a sharp rise in the temperature of the primary and secondary coil, which may soon burn the transformer coil. The detection method of partial discharge of transformer in busbar processing machine is generally electric measurement. Using oscillograph or radio interferometer to find the characteristic waveform of discharge or radio interference degree. Ultrasonic method. Detect the sound wave in the discharge, and convert the sound wave into electrical signal, recorded on tape for analysis, using the difference in the transmission time of electrical signal and sound signal, can get the distance from the detection point to the discharge point. Chemical measurement. Detect the content of dissolved gases in oil and the law of increase and decrease. The test detects changes in composition, proportion and quantity of oil to determine partial discharge (or partial overheating). In addition, in recent years, a partial discharge on-line detector has been developed, which can automatically detect partial discharge in transformer operation. In order to prevent the occurrence of partial discharge, the manufacturer should carry out reasonable structural design of the transformer; Careful construction, improve material purity, strict treatment of the quality of each link. Operation units should strengthen transformer maintenance and monitoring to effectively prevent partial discharge of transformer.