Research On Key Technologies Of 30kW Pihotovoltaic Power Grid-connected System

With the accelerated development of society today,the demand for energy consumption is increasing,and there is little left for fossil energy consumption,and it has caused serious environmental pollution problems.With the increasing maturity of photovoltaic power generation technology and the lower cost of power electronic devices,it is more conducive to the development of photovoltaic power generation.This article mainly analyzes the 30 kW photovoltaic grid-connected system,describes and tests its important components such as maximum power point tracking,grid-connected inverter control algorithm selection,island effect detection and other important components.(1)Brief Tell about the research role of this article,growth at home and abroad,and the prospects for future development,a simple classification of Photovoltaic power generation system based on different structures,and the operation of solar photovoltaic power generation The process is briefly described.(2)Introduce the mathematical model and working characteristics of photovoltaic cells,and give a detailed description of the structure of photovoltaic grid-connected inverter.For the unstable output power of photovoltaic cells affected by the outside world,the maximum power point tracking is required.This paper proposes an improved particle swarm and cuckoo search hybrid algorithm for maximum power point tracking.First,Improved particle swarm algorithm and the particle swarm optimization accuracy is also improved while accelerating particle convergence.Then the cuckoo algorithm's preference of random wandering is transferred to the improved particle swarm,so that the particles can jump out of the local maximum,improving the search efficiency(3)The control strategy of the three-phase photovoltaic grid-connected inverter is introduced,and the structure of the photovoltaic control system and the control method of the inverter are selected.Finally,simulation and verification of photovoltaic grid-connected system in Simulink.(4)The causes and hazards of island effect are introduced,and then the principles of active and passive island detection methods are briefly described.A bidirectional fast active frequency shift islanding detection method is proposed,and simulation verification is carried out to prove the correctness of the proposed algorithm,which can detect islands faster.(5)Based on the analysis of the photovoltaic grid-connected system,the hardware and software parts are designed.Introduce the development environment CCS of DSP,the selection of component parameters,etc.