This paper pass to analysis of FFT algorithmic and the complex number operation &derivation of instantaneous power for the three phases electric power system.

• 通过对FFT算法的分析及三相电力系统瞬时功率的复数运算推导,简要说明如何利用FFT算法分解出的电力系统的电流电压量进行两相式功率的测量。