In the scope of solar energy-based electrical needs in rural tropical regions, the present article develops and confronts experimental power models from the using of manufacturer data and a new model made with the met...In the scope of solar energy-based electrical needs in rural tropical regions, the present article develops and confronts experimental power models from the using of manufacturer data and a new model made with the meteorological and electrical data acquired. These data are registered through an acquisition station around a monocrystalline photovoltaic panel, designed and realized in the scope of this work. After the acquisition of meteorological data, a choice of the most relevant meteorological variable as input vectors to express the output powers obtained was carried out. Around the Single-Diode model, seven models are performed with analytics equations, iterative methods and an optimization method with a multi-objective function to get internal parameters. The proposed experimental model is made by a combination of the solution got at STC of an iterative method, with the value of nameplate and the use of an open circuit voltage equation with experimental coefficient to predict power output in operating conditions, and it’s demonstrated more efficient. The optimization of a multi-objective function using Nonlinear Squares (NLS) through the Leveng-Marqued method to solve the parameter estimation of a PV panel has been well done and the results are useful, like classic iterative method and less time-consuming.展开更多
In this paper, we present a noise removal technique by combining the P-M model with the LLT model. The combined technique takes full use of the advantage of both filters which is able to preserve edges and simultaneou...In this paper, we present a noise removal technique by combining the P-M model with the LLT model. The combined technique takes full use of the advantage of both filters which is able to preserve edges and simultaneously overcomes the staircase effect. We use a weighting function in our model, and compare this model with the P-M model as well as other fourth-order functional both in theory and numerical experiment.展开更多
Nonlinear elasticity of the earth medium produces a numerical difference between the dynamic and the static modulus of rock. The dynamic modulus is calculated with the ultrasonic velocity measurement, the small-cycle ...Nonlinear elasticity of the earth medium produces a numerical difference between the dynamic and the static modulus of rock. The dynamic modulus is calculated with the ultrasonic velocity measurement, the small-cycle modulus is calculated with small cycles in the load-unload experiment,the static modulus is calculated from the slope of the stress-strain curve in the large cycle, the Young’s modulus is obtained from the ratio of stress to strain in the measured point. The relationship between the modulus and the strain amplitudes is studied by changing the strain amplitude in the small cycles. The moduli obtained from different measuring methods are thus compared. The result shows that the dynamic modulus is the largest, the small-cycle modulus takes the second place, the static modulus of bigger-cycle is the third, and finally the Young’s modulus is the smallest. Nonlinear modulus of rock is a function of the strain level and strain amplitude. The modulus decreases exponentially with the ascending of the strain amplitude, while increases with the ascending of the strain level. Finally, the basic concept of the P-M model is briefly introduced and the relationship between the modulus and strain amplitude is explained by the rock having different distribution densities and the different open-and-close stresses of the micro-cracks.展开更多
文摘In the scope of solar energy-based electrical needs in rural tropical regions, the present article develops and confronts experimental power models from the using of manufacturer data and a new model made with the meteorological and electrical data acquired. These data are registered through an acquisition station around a monocrystalline photovoltaic panel, designed and realized in the scope of this work. After the acquisition of meteorological data, a choice of the most relevant meteorological variable as input vectors to express the output powers obtained was carried out. Around the Single-Diode model, seven models are performed with analytics equations, iterative methods and an optimization method with a multi-objective function to get internal parameters. The proposed experimental model is made by a combination of the solution got at STC of an iterative method, with the value of nameplate and the use of an open circuit voltage equation with experimental coefficient to predict power output in operating conditions, and it’s demonstrated more efficient. The optimization of a multi-objective function using Nonlinear Squares (NLS) through the Leveng-Marqued method to solve the parameter estimation of a PV panel has been well done and the results are useful, like classic iterative method and less time-consuming.
文摘In this paper, we present a noise removal technique by combining the P-M model with the LLT model. The combined technique takes full use of the advantage of both filters which is able to preserve edges and simultaneously overcomes the staircase effect. We use a weighting function in our model, and compare this model with the P-M model as well as other fourth-order functional both in theory and numerical experiment.
基金The project was funded by the National Natural ScienceFoundation,China (Item No.40274057) .
文摘Nonlinear elasticity of the earth medium produces a numerical difference between the dynamic and the static modulus of rock. The dynamic modulus is calculated with the ultrasonic velocity measurement, the small-cycle modulus is calculated with small cycles in the load-unload experiment,the static modulus is calculated from the slope of the stress-strain curve in the large cycle, the Young’s modulus is obtained from the ratio of stress to strain in the measured point. The relationship between the modulus and the strain amplitudes is studied by changing the strain amplitude in the small cycles. The moduli obtained from different measuring methods are thus compared. The result shows that the dynamic modulus is the largest, the small-cycle modulus takes the second place, the static modulus of bigger-cycle is the third, and finally the Young’s modulus is the smallest. Nonlinear modulus of rock is a function of the strain level and strain amplitude. The modulus decreases exponentially with the ascending of the strain amplitude, while increases with the ascending of the strain level. Finally, the basic concept of the P-M model is briefly introduced and the relationship between the modulus and strain amplitude is explained by the rock having different distribution densities and the different open-and-close stresses of the micro-cracks.
