The Research Of Control Strategy Of50kW DC Micro-grid In Yunnan Science And Technology Park

Micro-grid as a a powerful way for distributed energy into grid has filled a an important role in security and stability of power grid. The AC micro-grids is difficult to control because of problem of frequency and reactive power. With the apper of more and more DC power load and the load demand for high quality power, it makes more obvious advantages of DC micro-grid. The main work of this paper is as follows.(1) This paper describes a concept of DC micro-grid, and discusses the various advantages of DC micro-grid, analysis the characteristics of the micro-power in DC micro-grid and the important role of energy storage devices.(2) Study the control strategies of two-way DC inverters, batteries and photovoltaic cells in DC micro-grid. On the background of the project of Yunnan Power Grid Corporation50kW DC micro-grid in Yunnan Science and Technology Park, clear its control requirements of each unit in it, and clear the control principles of grid mode inverter control, off-grid mode battery control.(3) It established a simple model of the DC micro-grid using Matlab/simulink simulation software. In grid connection and grid disconnection, complete the simulation of the stability of the DC bus voltage in the case of the DC load suddenly increased and photovoltaic power generation suddenly reduced. Simulation results show that, it can guarantee the stability of the DC bus voltage, and provide high-quality electricity through the rational control at the same time, in the case of several typical run.