Study On Fault Diagnosis Of Photovoltaic Array Based On The State Of The Bypass Diode

Solar energy is the most promising new energy,with the rapid development of photovoltaic industry in the world,photovoltaic power station system in photovoltaic status monitoring and fault diagnosis becomes more and more important,as it relates to the operation state of photovoltaic power plants and photovoltaic power plant safety.At present,domestic and foreign scholars on the research of PV array fault diagnosis,by adding more sensors to detect different measurement points of photovoltaic array signal to realize the fault detection,and in practice,little light volt power plant using the complex circuit connection structure,because it is not conducive to the maintenance and safety is not high.Common fault diagnosis methods of photovoltaic cells can be divided into two categories:electrical signal diagnosis method and infrared image diagnosis method.These two methods are the external characteristics by detecting solar cell to fault analysis.In this paper,as little as possible into voltage and current sensor,photovoltaic cells based on the theory of fault diagnosis of photovoltaic PV system in tandem.Single diode photovoltaic cells based on mathematical model,through the establi_shment of parametric equations,the output of the I-V model of photovoltaic module theoretically.In the fourth chapter of this paper describes the data acquisition system based on ARM chip.The software system is designed based on the hardware circuit,which is used for data transmission,display and storage,and the data monitoring interface is realized by LabVIEW software.Finally,this paper analyzes the common fault types:open circuit fault,short circuit fault,shielding failure.In the fifth chapter,According to the I-V output single PV module and serial PV module,the theoretical model of the photovoltaic output serial I-V.Numerical analysis of photovoltaic tandem theory I-V output and measured output based on I-V,after the analysis of the voltage and current of the three faults,the fault judgement algorithm is given.And under occlusion in tandem photovoltaic bypass diodes conducting the number of estimates.