在分析现有面积等效方法的基础上，提出了一种面积中心等效法。按面积中心等效法合成的波形与传统的面积等效法合成的波形相比，其基波分量增大，低次谐波分量明显改善。我们参加09年国赛光伏并网发电模拟装置就是采用本方法产生SPWM波，效果很好。-In the analysis of the existing methods based on the equivalent area, a space center to follow. Follow by space center synthetic waveforms and the equivalent area of traditional synthetic waveforms compared to the fundamental component increases, lower harmonic components improved significantly. We participated in 2009 national competition PV power simulator is SPWM waves generated by this method, works well.