Integrated Droop Control Strategy for Parallel Operation of Solid State Transformers in Intelligent Distribution Network

Solid state transformer is a new type of power equipment which is expected to replace the traditional distribution transformer. It can satisfy the custom power demand of the renewable energy utilization and the high reliability of power supply. In intelligent distribution network with a large number of flexible equipment and impact load, the parallel operation of solid state transformers not only needs to consider the power distribution problem, but also needs to consider the power quality problems caused by these harmonic sources. An integrated droop control method is proposed in this paper, which not only realizes the active and reactive power distributed according to the capacity ratio, but also effectively suppress the harmonic current caused by the nonlinear load and ensure the power quality of the low-voltage AC bus. Matlab/Simulink simulation results show the validity and advantage of the proposed method, compared with the classic droop control method.