This paper analyses influence of inductance and capacitance to system , resonance of filter and output characteristic of inverter . after analyse the characteristic of inverter parallel system , form parallel system by current - controlled two state modulation inverters , and realize current sharing by pll and current - sharing circuit 分析了滤波电感和电容对系统的影响,并对输出滤波器的谐振现象和逆变器的外特性进行了深入的研究,证明了该调制技术抑制谐振的优点,指出了影响逆变器外特性的主要因素。