Abstract: Due to the microgrid loses the support of the large power grid when it is operating in an island, the stability of the system voltage and frequency is difficult to be guaranteed, and ensuring that the frequency and voltage of the system are maintained at a stable value is the prerequisite and basis for the stable operation of the microgrid. In view of the fact that the traditional droop control is likely to cause deviations in the frequency and voltage of the system, a state observer based on the PD control consistency algorithm is introduced in the secondary layer of the microgrid to dynamically compensate the deviation. The third layer aims to achieve the optimal economic operation of distributed power sources. The consensus algorithm theory of PD control is used to solve the optimal incremental rate and power value of distributed power sources. Compared with the basic consensus algorithm, the convergence time is effectively shortened. To further solve the optimal power value considering the limited conditions of distributed power generation, the stability simulation of the system is carried out for the load and power fluctuation factors in the end. Experiments are conducted to verify the effectiveness of the control strategy.