The Research Of Control Strategy In Off-grid Wind And Solar Hybrid System

Among the new energy,wind and solar energy are vigorously developed with its unique advantage,and become the most mature new energy in current technology utilization.But,they also have some disadvantages.For example,poor stability and greatly influenced by the weather,etc.In order to improve energy efficiency maximumly,takes advantage of the complementary property of wind and solar energy in the time and the region,combines them together and forms the wind and solar hybrid power generation system.With the continuous development of new energy technology,wind and solar hybrid power generation system will be widely used in the field of new energy as a kind of stable power supply system.In this thesis,introduces the whole structure of the off-grid wind and solar hybrid power generation system firstly,includes the basic operation principle and output characteristics of solar photovoltaic cell,wind turbine and battery.Then,establishes the simulation model of solar photovoltaic cell and wind turbine in the Matlab/Simulink environment,conducts a research of perturbation and observation method by using the boost conversion circuit,aiming at the problem of step length of perturbation and observation method,comes up with an algorithm of maximum power point tracking based on fuzzy control.This paper designs fuzzy controllers for solar photovoltaic system and wind power generation system,and achieves its maximum power tracking control,verifies the effectiveness and feasibility of fuzzy control in wind and solar hybrid power generation system by simulation in Matlab/Simulink environment. Finally, puts forward a control strategy of three-stage charging of battery.