摘要：本文對工頻機型UPS的輸出變壓器的作用進行了系統的探討，由分析得知，輸出變壓器并沒有那么多的作用，沒有輸出變壓器的高頻機型UPS同樣具有優良的穩壓性能。 敘詞：UPS 高頻機 工頻機 輸出變壓器 穩壓 Abstract：The article discusses systematically the function of out-put transformer of industrial frequency UPS and from the discussion, it is revealed that the function of out-put transformer is over-estimated. High-frequency UPS without out-put transformer also has excellent performance for stabilizing voltage. Keyword：UPS, High-frequency machine, Industrial-frequency machine, Out-put transformer, Voltage stabilizing