Large data processing centers need to match UPS (Uninterruptible Power System) power supply systems, but in the system design of UPS, the harmonic currents from the input terminal may influence the other devices of the power distribution system. Taking the power supply system of the Beijing Meteorological Satellite Ground Station as an example, the emergency power supply situation is analyzed while the satellite receiving antenna tracking satellite, and there appeared obvious dithering in the drive motor, which was induced by the harmonic currents of UPS. The principles and the influence of UPS power supply working on the electric power distribution system are introduced, and the design of an active filter to eliminate electric power harmonic influence and the method to reduce antenna drive motor dithering are described. The expansion trends of electric power harmonic waves induced by new rectification power supply technology are discussed.