Current measurements across a nematic cell submitted to an external voltage and its equivalent electrical circuit

2008 ◽  
Vol 461 (1-3) ◽  
pp. 164-169 ◽  
Author(s):  
R. Atasiei ◽  
A.L. Alexe-Ionescu ◽  
J.C. Dias ◽  
L.R. Evangelista ◽  
G. Barbero
2011 ◽  
Vol 158 (3) ◽  
pp. A326 ◽  
Author(s):  
T. K. Dong ◽  
A. Kirchev ◽  
F. Mattera ◽  
J. Kowal ◽  
Y. Bultel

Energies ◽  
2018 ◽  
Vol 11 (9) ◽  
pp. 2305 ◽  
Author(s):  
Yunhe Yu ◽  
Nishant Narayan ◽  
Victor Vega-Garita ◽  
Jelena Popovic-Gerber ◽  
Zian Qin ◽  
...  

The past few years have seen strong growth of solar-based off-grid energy solutions such as Solar Home Systems (SHS) as a means to ameliorate the grave problem of energy poverty. Battery storage is an essential component of SHS. An accurate battery model can play a vital role in SHS design. Knowing the dynamic behaviour of the battery is important for the battery sizing and estimating the battery behaviour for the chosen application at the system design stage. In this paper, an accurate cell level dynamic battery model based on the electrical equivalent circuit is constructed for two battery technologies: the valve regulated lead–acid (VRLA) battery and the LiFePO 4 (LFP) battery. Series of experiments were performed to obtain the relevant model parameters. This model is built for low C-rate applications (lower than 0.5 C-rate) as expected in SHS. The model considers the non-linear relation between the state of charge ( S O C ) and open circuit voltage ( V OC ) for both technologies. Additionally, the equivalent electrical circuit model for the VRLA battery was improved by including a 2nd order RC pair. The simulated model differs from the experimentally obtained result by less than 2%. This cell level battery model can be potentially scaled to battery pack level with flexible capacity, making the dynamic battery model a useful tool in SHS design.


2020 ◽  
Vol 20 (8) ◽  
pp. 4884-4891
Author(s):  
Rawiwan Chaleawpong ◽  
Nathaporn Promros ◽  
Peerasil Charoenyuenyao ◽  
Phongsaphak Sittimart ◽  
Satoshi Takeichi ◽  
...  

Coaxial arc plasma deposition (CAPD) was employed to manufacture n-type silicon/boron-doped p-type ultrananocrystalline diamond heterojunctions. Measurement and analysis of their dark current density-voltage curve were carried out at room temperature in order to calculate the requisite junction parameters using the Cheung and Norde approaches. For the calculation based on the Cheung approach, the series resistance (Rs), ideality factor (n) and barrier height (Φb) were 4.58 kΩ, 2.82 and 0.75 eV, respectively. The values of Rs and Φb were in agreement with those calculated using the Norde approach. Their characteristics for alternative current impedance at different frequency values were measured and analyzed as a function of the voltage (V) values ranging from 0 V to 0.5 V. Appearance of the real (Z′) and imaginary (Z″) characteristics for all V values presented single semicircles. The centers of the semicircular curves were below the Z′ axis and the diameter of the semicircles decreased with increments of the V value. The proper equivalent electrical circuit model for the manufactured heterojunction behavior was comprised of Rs combined with the parallel circuit of resistance and constant phase element.


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