The LVRT Research Of The Micro Power Based On DFIG In Micro-grid

With the rising of energy crisis and environmental degradation, the development of new energy is regarded as one of the important methods to deal with this issue all over the world, the technology of micro grid which based on new energy is developing rapidly, the connection of the micro grid is bound to brings many problems to the stability of power system, the LVRT ability of micro power is necessary condition to keep the micro grid system operating safely.Firstly, contrapose the control strategy of micro grid, comparison and research is made in the article. Secondly, the micro grid system with the doubly-fed wind power as the core is established in the MATLAB environment then the simulation of common wind speed model is made. great research is done on the LVRT ability of DFIG unit in the micro-grid, Tandem type and parallel type LVRT auxiliary device is installed in the micro grid connection point, the effect of the device, including the improvement of both the voltage stability of micro grid system and the LVRT ability of the DFIG unit is studied respectively, the method of installing DVR-STATCOM in units exit is put forward in this paper to bring down the output power fluctuation, improving the voltage stability of micro network system.Finally, based on the micro network model once built, the feasibility of the above method is verified by simulation, the simulation results show that the DVR-STATCOM method in this article has obvious effect in improving system voltage stability, smoothing power fluctuations and improving the LVRT ability of micro power.