Abstract: Aiming at the problems of three-phase load imbalance，power quality degradation and harmonic

dispersion in current electronic power distribution system，a comprehensive power quality control scheme with fast

dynamic response and small output harmonic was proposed，which includes comprehensive control mode and

compound repeat control strategy. By example analysis，it is found that harmonic content decreases before and after compensation in a specific subharmonic compensation mode. After the unbalanced grid compensation，the current distortion was eliminated and the voltage and current were in the same phase，which indicates the effectiveness of the comprehensive management. In the experimental verification，the continuous output of 25 kW inductive reactive power to 25 kW capacitive reactive power was realized ，the requirements of reactive power regulation -100%~100% in the technical index was met，and the deviation between the output power and the command value was only 0.49%，the requirements of less than 3% in the technical index were met. In addition，the compensated three-phase grid current THD was reduced to 4.7%，after unbalance compensation treatment，the unbalance degree was reduced to 1.4%，which shows the effectiveness of the device in the treatment of three-phase load unbalance，power quality degradation and harmonic dispersion.

      Key words: comprehensive treatment of power quality；power electronics technology；three-phase load imbalance；compensation of imbalance