Research On Fault Diagnosis And Location Method Of Photovoltaic Array Based On Detection Structure Optimization And Model Parameter Identification

Since the new century,with the progress of science and technology and the promotion of new energy,the solar photovoltaic power generation industry has been developed rapidly.As an important part of photovoltaic system,the working state of photovoltaic array has an important influence on the stable operation of photovoltaic power station,which makes the monitoring and fault diagnosis of photovoltaic array working state very important.In this paper,the existing photovoltaic array fault detection methods are analyzed.In order to reduce the detection cost and improve the real-time and universality of the diagnosis method,the detection optimization structure based on series-parallel(SP)connection mode is established,and the mapping relationship between photovoltaic output eigenvalues and fault state is proposed to realize the accurate location of shortcircuit and open-circuit fault components in photovoltaic array.In order to solve the problem that the model parameters of photovoltaic cells are greatly affected by the external environment,a fault location method based on the external and internal characteristic parameters of the model is proposed,which can accurately locate the fault components of short circuit,open circuit and local shade in different environments.The feasibility of the proposed method is proved by NI Multisim circuit software simulation.In view of the need to extract the internal model parameters of photovoltaic cells in photovoltaic fault diagnosis and location,a hybrid intelligent optimization algorithm based on collaborative interaction is proposed in this paper,which solves the problems of single internal parameter identification method,easy to fall into precocious and slow convergence speed,and effectively improves the performance of parameter identification.In this paper,the photovoltaic analog array experimental platform is built and the data acquisition system is designed.The fault diagnosis method proposed in this paper is used to diagnose and locate the short circuit,open circuit and local shading fault components in several test environments,and good results are obtained.It is proved that the detection structure and location method proposed in this paper can accurately locate the fault components in photovoltaic arrays in different environments under the premise of reducing the number of sensors,and do not need historical data and complex model training,and are easy to be extended to different photovoltaic arrays.