Research On Two-Stage Vibration Isolation Design Method Of Indoor Distribution Substation Facilities

More and more power distribution rooms and transformer substations of power facilities were set nearby residential buildings, which inevitably causes some problems of vibration and noise pollution. Some of the power distribution rooms were even placed into the basement of the residents or the next room to residents’room, which seriously affected residents’ normal life. In this paper, the two-stage vibration isolation method was used to solve the problem of structural noise caused by indoor transformer rooms, and the dynamic characteristics of the two-stage vibration isolation system were studied. According to the practical application, the influence of vibration isolation parameters on the vibration isolation effect was discussed, and a relatively complete design method of two-stage vibration isolation device was formed. The main contents are as follows:(1) A mechanical model of two-degree of freedom was simplified as a two-stage vibration isolation system. The influences of main vibration isolation parameters, like the mass ratio, stiffness ratio, and damping ratio on the force transfer rate of the double layer vibration isolation system were discussed. At the same time, based on the practical application of transformers and the mechanical model of two-degree of freedom, this paper discussed the influences of elasticity of the flexible foundation, the intermediate mass block, and the non-rigid characteristic of vibration isolation object on double-layer vibration isolation system of force transfer rate.(2) The design flow of two-stage vibration isolation device and the range of design parameters were summarized based on the summary of structure characteristics of dry type transformer and the influence of vibration isolation parameters on force transfer rate in two-stage vibration isolation system. Through the model tests, the vibration isolation effect of the two-stage vibration isolation system was verified.(3) The vibration isolation effect of the designed device was predicted based on the force transfer rate fomiula of the two-degree of freedom two-stage vibration isolation system. According to transformer’s actual situation, the influences of the elasticity of the flexible foundation, intermediate mass block and the non-rigid factors of vibration isolation object on the effect of vibration isolation were discussed respectively and the preliminary prediction results were optimized.(4) Based on a kind of common dry type transformers, several vibration isolation devices were designed and made out. The experimental results showed that one of these device, two-stage vibration isolation platform, had a good vibration isolation effect on the main vibration frequency of dry type transformer. The predictive value was modified appropriately based on the experimental results.