Control and operation of hybrid solar/wind isolated DC micro grid

DC microgrid is an effective solution for integrating distributed generation and various loads, which can reduce the impact on power system caused by the penetration of renewable energy systems. In this paper, control and operation of an isolated dc micro grid which consists of PV systems, wind turbines, energy storage and DC loads is investigated. Based on autonomous DC bus voltage control which contains an improved phase shift control and dual-loop control, the proposed control strategy effectively coordinates wind, solar and energy storage on the basis of the voltage of dc bus during various operating conditions. In addition, this paper realizes the electrical isolation of battery and DC bus by using isolated DC/DC converter. Psim/Simulink simulations validated the dc micro grid can maintain stable under the proposed control system.