Research On Capacity Optimization Of Wind/Solar Hybrid Power System And Photovoltaic Maximum Power Point Tracking

With the growing of global energy crisis,the development of new energy technologies has become a hot topic in the world.Solar energy and wind energy has gradually become two main kinds of new energy.Economy problem is still one of the main factors restricting the development and application of solar power and wind power generation.In order to improve the economy,this paper mainly studies the capacity optimization technology of off-grid wind-solar hybrid power generation system and photovoltaic system maximum power tracking technology.According to the complementarity of wind power and photovoltaic power generation,this paper introduces the advantages of wind-solar hybrid power generation technology.At the same time,the development status of wind-solar hybrid power generation system is summarized.Then,the model and characteristic of wind power generators,photovoltaic cells and energy storage batteries in wind-solar hybrid power generation system are built and analyzed.The operation mode of off-grid wind-solar hybrid power system is also introduced.Reasonable capacity configuration is of great significance to the economy and reliability of off-grid wind-solar hybrid power system.In this paper,the capacity optimization model of off-grid wind-solar hybrid power generation system is established,taking the minimum annual loss of power supply probability and the lowest cost of the system as the objective function,taking the battery charge-discharge times,the system power balance and so on as restrictions.Aiming at the contradictoriness characteristic of loss of power supply probability and system cost,the concept of crowding degree and Pareto order are introduced into the complex differential evolution algorithm,which makes the improved algorithm have multi-objective optimization ability.Finally,the algorithm is used to solve the optimal configuration model of the wind power complementary system.The results of the example verify the rationality of the model and the effectiveness of the proposed algorithm.The maximum power tracking technology of photovoltaic system has a great influence on the efficiency of photovoltaic power generation.Under the partially shaded conditions,the output characteristics of the photovoltaic array exist a number of extreme points and the traditional maximum power tracking technology is no longer applicable.In this paper,the development status of photovoltaic system maximum power tracking technology is reviewed.Then the modeling and characteristic analysis of photovoltaic arrays are carried out.At the same time,the multi-extreme value problems under partially shaded conditions that may occur during maximum power tracking are analyzed and modeled.In order to solve the problem that the particle swarm optimization algorithm may converge at a local maximum caused by initial value being improperly set,the chaotic particle swarm optimization algorithm is introduced into the optimization problem.The results of the example under several shadow conditions verify the model and algorithm.