| The replacement of traditional petrochemical energy with renewable green energy has become the development trend of the world today,and it is a key research topic that people will pay attention to for a long time.Among the renewable green energy sources,solar energy is undoubtedly the most ideal,but its power generation efficiency has been limited by the photoelectric conversion capability of photovoltaic arrays.The characteristics of photovoltaic arrays depend on the influence of materials and processes.It is difficult to make breakthroughs in technology in a short period of time.It is unrealistic to rely solely on photovoltaic power generation systems to improve power generation efficiency.Therefore,it is necessary to study the power generation efficiency improvement method from the peripheral technology of the photovoltaic power generation system to improve the power generation efficiency.At present,there are two main technical paths:the maximum power point algorithm and the solar position tracking for improving the photoelectric conversion efficiency and solar energy utilization rate of photovoltaic systems.However,there are still problems in technology and methods in specific applications,which affect the improvement effect.It mainly includes the lack of special sensors for sunlight position detection.It also needs to consider the influence of light intensity and temperature and humidity changes on the tracking effect,and the MPPT maximum power point algorithm optimization problem.The maximum power point algorithm generally adopts an open-loop control mode,which leads to error accumulation,and also needs to recalculate the tracking trajectory according to the regional change,resulting in complicated operation process and the like.Based on the above considerations,this paper focuses on the methods and technical problems in the application of PV array automatic tracking system,from the photovoltaic generator technology,automatic tracking system,solar azimuth sensing sensor,MPPT maximum power point algorithm and other aspects of optimization design and in-depth research.The photovoltaic mechanism and electrical parameter output model of solar cells were studied,and the PV array engineering model under working conditions and the model considering avalanche effect were constructed.Through the basic analytical expression of electrical characteristics,the reasons for the electrical characteristics under the influence of illumination and temperature are analyzed,and the necessity of adopting the automatic solar tracking method to improve the efficiency of photovoltaic power generation is discussed.Based on the comprehensive analysis and tracking method,an intelligent integrated tracking method based on intelligent photoelectric sensor tracking method and visual-day trajectory tracking method is proposed.The theoretical value of lifting efficiency is calculated,and the output model law affected by light intensity variation and temperature is studied.For the current intelligent photoelectric sensor tracking method,the visible light sensor is used to sense the sunlight.When the visible light is weak,the detection sensitivity of the sensor is decreased,and the tracking system cannot work.At this time,there are infrared and other invisible light in the sunlight,and the tracking system can be continuously driven by detecting infrared light.A new photoelectric sensor with lateral photoelectric effect and combined C32H16N8Cu and CdS has been developed to solve the problem of both infrared and visible light.The mechanism of lateral photoelectric effect of PSD is analyzed,and the relationship between the electric field on the surface of the sensor film and the vertical arrangement function in the X and Y directions is established.The naturalization process calculates the coordinate system of X and Y.Analyze the characteristics of photosensitive materials,study the process of photosensitive materials and sensor chips,design the package structure of the modulated light spots combined with the polarizing plate and the light-shielding cylinder,and develop and optimize the packaging mode of the sensor light-shielding cylinder.The method of tracking the position of the sun is discussed to realize the correspondence between the visible light position and the coordinate system,and the sensor signal output conditioning model is constructed to realize the wide range of detection of the sunlight position.According to the nonlinear relationship between the output power of the photovoltaic cell and the temperature and the light intensity,a closed-loop control strategy is adopted to give full play to the maximum power output of the photovoltaic cell.Based on the analysis of the model characteristics of the maximum power point,the MPPT tracking method of the disturbance observation method is proposed.The disturbance observation method model is constructed and optimized,and the power variation?P and the voltage variation?V disturbance mode of the light intensity change are given.The realization system and algorithm implementation flow of the disturbance observation method are designed,the simulation experiment model is constructed,and the disturbance observation algorithm is further optimized through the PID control link.The simulation results show that the steady-state current output characteristics can be obtained,the duty cycle variation of the model and the oscillation of the maximum power point voltage are significantly reduced,and the problems of system oscillation and overshoot are improved.The photoelectric sensor type solar automatic tracking system and PSD position sensor experimental device were designed and developed.The performance of the sensor and tracking system was evaluated by simulation experiments.The validity of the PPT position sensor sensing infrared,visible and disturbance observation MPPT tracking method was verified.The volt-ampere characteristics of the sensor chip are given.The resistance of the PbS infrared photosensitive cell changes by 37.5%.The C32H16N8Cu visible light sensitive cell exhibits triode characteristics.The Iec increases with the increase of the bias voltage Vec.The Iec brightness current ratio before and after illumination is 4.51.The packaged PSD position sensor analyzes the linear relationship between the illumination point displacement ratio Y and the angle.In the 90±10°measurement range,the illumination point angle error is<0.2°.Set up a tracking system experimental platform,complete the software and hardware and mechanical structure design,and carry out experimental verification according to local meteorological conditions.The results show that the photoelectric conversion efficiency of the tracking photovoltaic system is improved by 24.36%.After the MPPT tracking algorithm of the disturbance observation method is optimized,the photoelectric conversion efficiency is improved to 43.40%.The PSD position sensor and MPPT algorithm are optimized. |
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