Droop control is widely employed in the parallel connection of units within a microgrid, particularly in some specific environments. However, due to differences between units and the changeable point of common coupling, the line impedance of each unit is different, resulting in a poor distribution of the output power of each unit. An improved control strategy is proposed to realize power equalization between units without connecting them while the line impedance is resistance-inductance. The power information is exchanged between each parallel unit by injecting harmonics according to the reactive power of each unit and the corresponding phase angle. The small signal analysis of the parallel model determines the stability of the control system. Finally, the effectiveness of the proposed improved control strategy is verified via simulation and hardware-in-loop experiments.