Improvement of maximum power point tracking in photovoltaic arrays in different environments using hybrid algorithms

When the photovoltaic(PV)system is generating PV power,the partial shading(PS)condition will cause multiple peaks in the power-voltage curve,and changes in light intensity and ambient temperature will cause the curve to shift.Traditional maximum power point tracking(MPPT)methods,such as the incremental conductance(INC)method,have the problem of being trapped in the local optimal solution.Biomimetic optimization algorithms,such as particle swarm optimization(PSO),have problems with oscillation and low tracking efficiency near the global maximum power point(GMPP).As a result,a hybrid algorithm CS-INC based on the cuckoo search(CS)algorithm and the perturb and observe(P&O)approach is proposed in this study.The light intensity remains constant,the light intensity changes in steps,and the partial shade scenario are simulated.Simulation results show that the MPPT improves accuracy,speed,and stability.

Tuning the band gap of the CIGS solar buffer layer Cd_(1-x)Zn_(x)S(x=0—1) to achieve high efficiency

To evaluate the impact of zinc sulfate(ZnSO_(4)) concentration on the structural properties of the films,Cd_(1-x)Zn_(x)S thin films were formed on glass substrates using chemical bath deposition(CBD) in this study.The effect of ZnSO_(4) precursor concentration on the surface morphology,optical properties,and morphological structure of the Cd_(1-x)Zn_(x)S films was investigated.To study the impact of zinc doping content on the performance metrics of Cu(In_(1-x)Ga_(x))Se_(2)(CIGS)cells in the experimental group and to improve the buffer layer thickness,simulations were run using one-dimensional solar cell capacitance simulator(SCAPS-1D) software.

Tuning zinc doping content to optimize optical and structural properties of Cd1-xZnxS buffer layers

In this paper,Cd1-xZnxS thin films were prepared by chemical bath deposition(CBD),and the effects of different zinc doping content on the morphological structure and optical properties of Cd1-xZnxS buffer layers are systematically discussed.The experimental results show that in the deposition process of different substrates,the crystal structure of the film is all hexagonal,and when the concentration of zinc sulfate(ZnSO4)precursor is varied from 0 to 0.025 M,the films are uniform and dense.With the increase of zinc content,the X-ray diffraction(XRD)peak of the films shifted behind that of CdS film(002).It showed 70%to 90%transmittance in the visible region and the optical band gap increased gradually.The band gap value of the films obtained ranged from 2.43 eV to 3.01 eV.It shows the potential feasibility of its application to photovoltaic devices.

Effect of preheating and annealing temperature on the microstructure and optoelectronic properties of CZTS films prepared by sol-gel method

The effects of different preheating and annealing temperatures on the surface morphology,microstructure,and optical properties of Cu_(2)ZnSnS_(4)(CZTS) thin films are investigated by controlling the preheating and annealing temperatures.The prepared thin films were characterized using X-ray diffraction(XRD),Raman spectroscopy,scanning electron microscopy(SEM),and ultra-violet-visible(UV-Vis) spectroscopy techniques.XRD and Raman spectroscopy showed that a Kesterite structure with a selective orientation along the(112) peak was generated,and the thin films produced at a preheating temperature of 300℃ and annealing temperature of 570℃ had fewer secondary phases,which was beneficial for improving the performance of the solar cells.SEM confirms that the crystallite size increases and then decreases as the temperature increases,and the largest and most uniform crystallite size with the smoothest surface is generated at the above preheating and annealing temperatures.UV-Vis measurements show that the thin films generated at the above temperature have the lowest transmittance and the lowest optical band gap value of 1.46 e V,which is close to the optimal band gap value for solar cells and is suitable as an absorber layer material.

Structural,electrochemical and cycling properties of Nb^(5+)doped LiNi_(0.8)Co_(0.1)Mn_(0.1)O_(2)cathode materials at different calcination temperatures for lithium-ion batteries

LiNi_(0.8)Co_(0.1)Mn_(0.1)O_(2)cathode material is prepared by sol-gel method and the effects of Nb^(5+)doping and different calcination temperatures on cathode materials were deeply investigated.Structural and morphological characterizations revealed that the optimal content of 1 mol%Nb^(5+)can stabilize layered structures,mitigate Ni^(2+)migration to Li layers,improve lithium diffusion capacity,and reduce lattice expansion/shrinkage while cycling.And calcination temperature at 800℃can not only ensure good morphology,but also suppress the mixed discharge of lithium and nickel in the internal structure.Electrochemical performance evaluation revealed that Nb^(5+)doping improves the discharge-specific capacity of the material,which is conducive to ameliorating its rate capability and cycle performance.And the material at 800℃exhibits the highest discharge specific capacity,the best magnification performance,low polarizability,and the best cycle reversibility.

Effect of complexing agent concentration on properties of CdZnS thin films in ammonia-thiourea system

In this paper,the effects of different concentrations of complexing agent(ammonia)on the surface morphology,composition,structure and photoelectric properties of Cd Zn S films were studied.The results of X-ray diffraction(XRD),scanning electron microscopy(SEM)and UV-visible spectrum showed that the surface morphology of the films became worse and the content of zinc decreased significantly with the increase of ammonia concentration.The crystalline phase of Cd Zn S films was not influenced by the ammonia concentration.Because the film has good absorbance,transmittance greater than 70%and band gap width between 3.5 eV and 3.07 eV,it is suitable to be used as a buffer layer for solar cells.Cd S,Zn O and Zn(OH)_(2) were found in the precipitates at the bottom of the solution,and the formation of these precipitates affected the properties of the Cd Zn S films.