A control strategy based on improved structure of unified power quality conditioner（UPQC）is proposed for 380 V three-phase four-wire microgrids.The strategy can effectively compensate voltage sags，voltage swells and voltage distortion，as well as voltage power quality problems caused by nonlinear and unbalanced loads in the microgrid.Grid-side converters（including series converter and parallel converter）can compensate grid voltage and current，which not only solves the coupling interference from series and parallel converters，but also achieves proper load power distribution in the microgrid.An improved minimum-energy compensation method is proposed by improving the UPQC structure at the point of common coupling，overcoming the disadvantages of traditional compensation algorithm and ensuring no phase mutation of load voltage.It not only improves voltage compensation ability and range of distributed generators，but also reduces the capacity and cost of converters.MATLAB/Simulink simulation results verify the effectiveness of the proposed method.