Abstract: A multiple feedback loop control scheme is presented for single-phase power supply through sinusoidal inverter. The proposed outer control loop uses two PI controllers for the independent control as magnitude/phase to ensure a highly steady precision of the voltage output from inverted power supply. The inner control loop uses voltage output as a feedback to ensure a fast response to the voltage output and reduce waveform distortion. A new algorithm is proposed to detect the phase of sinusoidal voltage output from the inverted power supply so as to make the high-precision control of power supply inversion easy to implement. The simulation results verify that the control system based on the proposed method has excellent dynamic/static characteristics to keep all voltage output waveforms highly sinusoidal under any loading conditions.