A new method of the microprocessor control of three phase sinusoidal voltage pulsewidth modulated (PWM) inverters is proposed. First, the discretized state equations of the inverter main circuit on the d-q frame have been derived. An algorithm of the dead beat control with a current minor loop that constrains the inverter current within the safety limit, is subsequently developed. To compensate the computing time delay, the second order prediction method, and a new discretization method using twice time of the sampling period have been adopted. This method is especially suitable for inverters using high speed switching devices and digital signal processors.