Trial Research On UHF Partial Discharge Signal In Power Equipment

Because power equipment is an important part of the power system, the reliability of power equipment which it runs has a great significance for the safe operation of the power system. Partial discharge is one of the important factors to cause the insulation broken down and electrical equipment accidents. It has a great significance to detect early hidden faults and prevent insulation breakdown accident to research the method to detect the partial discharge signal and obtain the feature of the partial discharge signal by partial discharge trial.Based on UHF method, this paper has done the following work in view of the partial discharge.Firstly, a optimized Archimedean antenna was designed. The Gain, VSWR, Return loss and Axial ratio of this antenna are better than the existed Archimedean antenna and Complex planar spiral antenna.Secondly, a trial platform of partial discharge in the air was built. The partial discharge signals emitted from the electrostatic motor were received with the optimized Archimedes antenna. The signal was filtered by a wide-band filter and amplified by a 5 times amplifier. The signals was acquired and stored by the numerical oscilloscope, and analyzed by computer.Thirdly, compared with the acquisition results of partial discharge signals by Complex planar spiral antenna, the optimized antenna Archimedean had stronger ability to receive the partial discharge signals.The optimized Archimedean antenna was used to acquire the signals on the condition of different ball-gap and time-interval. It was founded that the discharged signals increased with the increase of ball-gap distance and time-interval.The trial system can acquire the UHF signals. It laid a solid foundation of on-line monitoring for UHF signals.