Research On Micro Grid Power Economic Planning And Improving Power Quality

The development of new energies and renewable energies is the trend of economic development in our country in the future. It is one of the directions of science and technology and rejuvenating the country. Because of the characteristic that micro grid system not only could run stand-alone but also could connect with large utility power grid. And it is one of the most important means of the application of new energies because of its own technological advantages. For the islands and some remote mountain areas, micro grid system not only could solve the located problem of power supply, but also decrease the cost of a large amount of power infrastructure construction. It would improve the life of remote areas flexible. The wind-PV-diesel-battery mode of hybrid renewable energy micro grid system is main form of these new energies demonstration projects. In this paper, with the objects of wind-PV-diesel-battery micro grid system, in accordance with the natural features of the island areas, we do the study of economy capacity research of optimal configuration of the micro grid systems and the improvement of power quality. The research work mainly includes:(1) Research of economy configuration of the distributed generations and control strategies.(2) The study of islands stand-alone micro grid system case.(3) Modeling of the micro grid system simulation with MATLAB.(4) Research of harmonic elimination of 3 phase active front-end converter with low carrier ratio.For the research of economy configuration of the distributed generations and control strategies, this paper has analyzed the micro grid system work principle and the performance characteristic of the generations. We do the key research of the characteristic of the economic operations of diesel generations. On basis of this work, we do the economy configuration of the distributed generations of island micro grid system with genetic algorithm(GA). According to the practical engineering application requirements, we concluded that it meets the needs of engineering of configuration optimization of distributed generations. HOMER simulation optimization is based on the genetic algorithm to optimize configuration of the theoretical results.According to the modeling problems of the distributed generations in micro grid system, this paper has built the diesel generators model and wind generators model. In addition, we have done some work with model of photo-voltaic connecting with grid. It laid down the foundation of the whole system simulation. For the diesel generators in parallel simulation running problem, the system can adjust the operations of the diesel generator strategy according to the load change, the demand trend of intelligent automation of electric power system were completed to a certain extent.Aiming at the problems of power quality improvement, this paper had done the study with three phases active front-end converters with low carrier ratio. The combination of SPWM and SVPWM carrier modulation scheme were proposed. The selective carrier frequency switches were designed. Considering the reduction of energy consumption of IGBT switch loss, harmonics are suppressed to a small degree.