Study On The Control Strategies Of Microgrid

Currently energy and environmental issues have become a key factor restricting social development, but distributed power generation technology can make a win-win situation for the energy conservation and environmental protection, so this kind of technology has become one of the important development directions in the electrical power industry. However there are also many problems with distributed power. In order to solve the contradiction between the power systems and distributed power, the conception of microgrid was proposed. And it has already become one of the most forefront topics in the international electrical engineering line.The project "Integrated control microgrid and the development and construction of experimental platform " funded by State Key Laboratory of Power Systems as the background in this thesis enables the main research of micro-grids integrated control strategy theory, simulation analysis and experimental platform development for control algorithm, and establishes the foundation for further research for micro-gridFirst, establish the microgrid equivalent model, to achieve the design method of PQ controller, V/f controller and synchronization grid controller. Describe the SVPWM's generation principle and implementation steps in details, use the engineering Tuning to settle PI parameters, meanwhile to design LC filter and three-phase voltage software PLL. In the end, use Matlab/Simulink simulation software to build the simulation model for micro-grid and control system. There is simulation analysis to verify the effectiveness and correctness of the control strategies according to 4 different operation characteristics.Second, establish the wind power systems, PV power generation systems and battery system etc three specific types of micro source models, by using the MPPT. Charge and discharge the battery according to the need reasonably. Finally, build the whole system model under the Simulink software, configure batteries at the exit port of wind and solar array respectively to stabilize grid power, as well as to act as the networking components under the isolated mode to absorb and supply wind light power after the complementation, and verify the feasibility of the control strategy according to the simulation resultsFinally, set up the micro source inverter experimental platform and design the system hardware and software. Verify the strategies correctness of the connected mode, disconnected mode, and converter between controller each other, cutting or increasing load in islanding mode.