短語詞組短語frequency y variation 頻率變動(dòng)frequency of variation 變異頻率frequency stabilization variation method 頻率變化法frequency instantaneous variation 高頻瞬變high frequency climatic variation 高頻氣候變化frequency stabilization variation 頻率變化high -frequency instantaneous variation 高頻瞬變power -frequency component variation 工頻變化量variable - frequency speed variation 變頻調(diào)速 返回 frequency variation