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Power transformer is an important equipment in the power system, which can transform voltage from one grade to other grade. Different electric networks are connected together by power transformer, the complex electric network or large electric power system is made up of. The power system developing towards extra high pressure 、 large electric network、 large capacity、 automatic direction, it is important to improve the reliability of power transformer. So people start to pay attention to the research the application of state-monitoring of transformer. Due to traditional methods join into the power system, existing fatalness. A new monitoring method attracts people attention, which is the method of power transformer vibration-monitoring, through vibration acceleration transducer which sticking on power transformer picking up the vibration signal, the monitoring method has no electric connection.The primary work is as follows in the paper:(1) Develop the vibration-monitoring system of transformer.Be dead against the characteristics of the vibration signal of transformer, choose vibration acceleration transducer、 charge-amplifier and the data pick-up equipment, also some techniques of anti-interference are adopted. Develop the software of vibration-monitoring of transformer base on LabWindows/CV Virtual Instrument. The software consists of data pick-up module、 signal analysis module、 displaymodule > the time domain eigenvalue measured module ^ data saved module and fault diagnosis module.(2) A testing transformer is chose to be the research object, research its vibration state under no-load and load. Indicate that.The result shows that, the transformer working under no-load condition, along with the no-load voltage increasing, the intensity of the vibration is stronger. The transformer working under load condition, when the second-side voltage is little, under the condition of the load current increasing, due to the limit of the equipment, the max load current is 0.08A, so the vibration created by load current is little, the intensity of the vibration is stronger go with the load current increasing. Under the condition of the load current and voltage increasing, the intensity of the vibration is stronger too. When the transformer working under load condition, the base frequency of the vibration signal is lOOHz, and contains other the high harmonic waves (200Hz, 300Hz and 400Hz,etc), around lOOOHz, frequency components are near zero.By using the monitoring system, it can indicate that this method is feasible to monitoring condition of the power transformer, it has well develop space to research.
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