Three-phase inverter is the conversion of the ac voltage phase, namely AC380V, three-phase electricity is made up of three same frequency, amplitude, phase difference of 120 ° to each other in turn equal exchange of electric potential.Is the definition of a three-phase inverter converts dc to ac power converter, the basic principle of SPWM , hardware architecture of four power module of single-phase, three-phase bridge type circuit, bridge between the output and load combination of low-pass filter element, the control circuit has two signal source, a triangular wave is fixed amplitude modulation wave generator, a sine wave generator, Sine wave to make use of the triangle wave modulation