Design Of Grid Connected Switch For Distributed Generation Based On Wind Power Generation

With the promotion of energy-saving and emission-reduction policy,the use of energy-saving new materials instead of high-energy consumption traditional materials has become the development trend of the design and manufacture of electrical equipment in the future.The deployment of the national strategies “Industry 4.0” and “Made in China 2025” has made the distributed wind power technology develop rapidly.As the main control switch in distributed wind power generation system,the reliability of grid connected switch will directly affect the stability of the wind power generation system.In this paper,a design scheme of a new type of distributed power grid connected switch is proposed by using the characteristics of high remanence of nano two-phase magnetic material,which solves the problems that traditional electromagnetic gridconnected switch has large power loss and cannot maintain when the grid voltage drops.According to the technical requirements of grid connected switch of wind power generation systems,the effects of different treatment temperatures and different compositional elements on the magnetic properties of the materials are studied.In combination with electromagnetic theory and empirical formulas,the material size and structure of the new grid-connected switch is calculated and determined.In order to accurately obtain the change regulation of each parameter of the new grid connected switch during the opening and closing process,the finite element simulation software is used to establish a three-dimensional solid model of the switch,and the dynamic and static characteristics are calculated and analyzed.The relationship between the working characteristics of the grid connected switch and the structural parameters such as the sectional width of the switch and the height of the core is obtained.In addition,the curves of moving speed,coil current,electromagnetic attraction and other parameters of the movable part in the process of opening and closing are also obtained.The simulation results show that the new grid connected switch can maintain the pull-in state without excitation current,which has better energy-saving effect than the traditional electromagnetic grid connected switch.Based on the above theoretical design and simulation analysis,a new grid connected switch prototype is made.Through the experimental platform built by voltage regulators,transformers,oscilloscopes and other instruments,the opening and closing test experiment has carried out.The experimental results verify the rationality of the design of the grid connected switch,which shows that the switch can be well applied to the wind power generation system and effectively improves the stability of grid connected operation of large scale distributed power.The design scheme has a certain theoretical significance and practical value.