Analysis of Vibration Characteristics of Mechanical Defects in GIS Three-Position Switch Travel not in Place Based on Multi-point Information

Mechanical defects in the travel of three-position switches not in place are an important factor in the failure of GIS equipment and a serious threat to grid security. In order to realise the effective operation and maintenance of mechanical defects in three-position switch travel, this paper builds a simulation platform for mechanical defects in travel using real three-position switches, studies the vibration law of the three-position switch breaking and closing action process under normal and energy resistance defects, and carries out a comparative analysis of the vibration characteristics and vibration parameters of three-position switches in different states with multiple measurement points in the time/frequency domain. The results show that: the vibration signal amplitude is related to the distance between the location of the measurement point and the location where the defect occurs; the normal three-position switch operates smoothly and has weak vibration amplitude and light pulses, while the impact tooth effect caused by the energy resistance defect produces a cyclic shock vibration signal with stronger vibration amplitude and longer transient action time; the absolute mean value of vibration in the time domain and the energy value in the frequency domain of the three-position switch defect are significantly greater than the normal state, based on which the qualitative determination of the presence or absence of defects can be effectively achieved.