scholarly journals Analysis of the impact of a flexible photovoltaic tile shape on its performance

2018 ◽  
Vol 44 ◽  
pp. 00085 ◽  
Author(s):  
Dariusz Kurz ◽  
Lena Morawska ◽  
Robert Piechota ◽  
Grzegorz Trzmiel
Keyword(s):  
Solar Radiation ◽  
Output Power ◽  
Inclination Angle ◽  
Short Circuit ◽  
Short Circuit Current ◽  
The Body ◽  
Building Integrated Photovoltaics ◽  
Base Measurement ◽  
The Impact ◽  
Power Curves

This paper addresses the subject of the building integrated photovoltaics (BIPV). The flexible thin-film CIGS module has been subjected to testing in order to investigate its electrical parameters and the possibilities of adaptation to the building structure. During analysis of performance of the tested building in real conditions, particular attention has been paid to changes in its parameters depending on the inclination angle and the shape of its surface in relation to the incident solar radiation. Current-voltage characteristics and power curves in the selected configuration of module deflections have been analysed. Changing the module’s inclination angle from the optimal 40° to 0° (horizontal arrangement of the module on the ground) reduced the value of generated current (by approx. 26%), voltage increase (by approx. 4%) and output power reduction by approx. 25%. The module generated a lower power compared to the basic test due to the irradiation limit reaching its surface (decrease in the irradiance value of less than 60% from 800 to 330 W/m2). Bending the module at an angle 90° to the ground affected the large unevenness of solar radiation values reaching its surface and even greater losses of generated energy. The values of idle voltage, short-circuit current and voltage in MPP did not change much in relation to the base measurement, however, a large drop in the value of current in MPP was noted, which led to a significant reduction of output power. Thus, the need to strive for the most advantageous exposure of BIPV elements in relation to the sun was demonstrated and the losses on energy yields resulting from the integration of photovoltaic tiles into the body of the building have been estimated.

Research of Large-Scale Offshore Wind Farm Collection System Short Circuit Equivalent Network

2013 ◽  
Vol 448-453 ◽  
pp. 1732-1737
Author(s):  
Liu Bin ◽  
Hong Wei Cui ◽  
Li Xu ◽  
Kun Wang ◽  
Zhu Zhan ◽  
...  
Keyword(s):  
Large Scale ◽  
Wind Farm ◽  
Short Circuit ◽  
Short Circuit Current ◽  
System Optimization ◽  
Offshore Wind ◽  
Offshore Wind Farm ◽  
Collection System ◽  
Medium Voltage ◽  
The Impact

This paper analyses the characteristics of large-scale offshore wind farm collection network and the impact of the medium voltage collection system optimization,while from the electrical technology point,it proposes the short circuit current of the collection network computational model and algorithms,based on the principle of equivalent circuit.Taking a wind power coolection system planned for a certain offshore wind farm planning for example, the validity of the model and algorithm is verified.

Analytical and Experimental Studies on Induced Current Switching by a Fault-Proof Gas Insulated Earthing Switch

2010 ◽  
Vol 11 (5) ◽  
Author(s):  
Mandava Mohana Rao ◽  
Moutusi Paul ◽  
H.S. Jain
Keyword(s):  
Short Circuit ◽  
Experimental Studies ◽  
Short Circuit Current ◽  
Design Parameters ◽  
Induced Current ◽  
Current Switching ◽  
Test Circuit ◽  
Reliable Performance ◽  
Gas Insulated Substation ◽  
The Impact

Fault-proof earthing switches are one of the important modules of a gas insulated substation, as it enables make at 100 percent short circuit current, which is functionally different from maintenance earthing switches. The fault-proof earthing switch shall be designed to make and break electro-magnetically and electro-statically induced currents as per IEC-62271-102. The paper discusses the impact of “test circuit configurations and voltage” on test parameters for gas insulated fault-proof earthing switch utilizing simulation with PSCAD software. Authors record the development of a 145 kV gas insulated fault proof earthing switch by considering novel design features like minimum arcing/pre-arcing time, effective current transfer from arcing contact to ground terminal, etc. The development has been evaluated successfully for electro-magnetically and electro-statically induced current duties as per IEC. Finally, design parameters to be considered for ensuring reliable performance during induced current switching from fault-proof earthing switches are also discussed.

Effect of luminal acidity on the apical cation channel in rabbit esophageal epithelium

2007 ◽  
Vol 292 (3) ◽  
pp. G796-G805 ◽  
Author(s):  
N. A. Tobey ◽  
C. M. Argote ◽  
M. S. Awayda ◽  
X. C. Vanegas ◽  
R. C. Orlando
Keyword(s):  
Short Circuit ◽  
Short Circuit Current ◽  
Acid Reflux ◽  
Cation Channel ◽  
Esophageal Epithelium ◽  
Protective Function ◽  
Membrane Area ◽  
Luminal Ph ◽  
The Impact

Esophageal epithelial cells contain an apical cation channel that actively absorbs sodium ions (Na+). Since these channels are exposed in vivo to acid reflux, we sought the impact of high acidity on Na+channel function in Ussing-chambered rabbit epithelium. Serosal nystatin abolished short-circuit current ( Isc) and luminal pH titrated from pH 7.0 to pH ≥ 2.0 had no effect on Isc. Circuit analysis at pH 2.0 showed small, but significant, increases in apical and shunt resistances. At pH < 2.0, Iscincreased whereas resistance ( RT) decreased along with an increase in fluorescein flux. The change in Isc, but not RT, was reversible at pH 7.4. Reducing pH from 7.0 to 1.1 with H2SO4gave a similar pattern but higher Iscvalues, suggesting shunt permselectivity. A 10:1 Na+gradient after nystatin increased Iscby ∼4 μAmps/cm2and this declined at pH ≤ 3.5 until it reached ∼0.0 at pH 2.0. Impedance analysis on acid-exposed (non-nystatin treated) tissues showed compensatory changes in apical (increase) and basolateral (decrease) resistance at modest luminal acidity that were poorly reversible at pH 2.0 and associated with declines in capacitance, a reflection of lower apical membrane area. In esophageal epithelium apical cation channels transport Na+at gradients as low as 10:1 but do not transport H+at gradients of 100,000:1 (luminal pH 2.0). Luminal acid also inhibits Na+transport via the channels and abolishes it at pH 2.0. These effects on the channel may serve as a protective function for esophageal epithelium exposed to acid reflux.

scholarly journals Cholera toxin enhances Na+absorption across MCF10A human mammary epithelia

2014 ◽  
Vol 306 (5) ◽  
pp. C471-C484 ◽  
Author(s):  
Qian Wang ◽  
Bruce D. Schultz
Keyword(s):  
Ion Transport ◽  
Cholera Toxin ◽  
Short Circuit ◽  
Mammary Epithelium ◽  
Brefeldin A ◽  
Short Circuit Current ◽  
The Body ◽  
Cellular Mechanisms ◽  
Mammary Epithelia ◽  
Mcf10a Cells

Cellular mechanisms to account for the low Na+concentration in human milk are poorly defined. MCF10A cells, which were derived from human mammary epithelium and grown on permeable supports, exhibit amiloride- and benzamil-sensitive short-circuit current ( Isc; a sensitive indicator of net ion transport), suggesting activity of the epithelial Na+channel ENaC. When cultured in the presence of cholera toxin (Ctx), MCF10A cells exhibit greater amiloride-sensitive Iscat all time points tested (2 h to 7 days), an effect that is not reduced with Ctx washout for 12 h. Amiloride-sensitive Iscremains elevated by Ctx in the presence of inhibitors for PKA (H-89, Rp-cAMP), PI3K (LY294002), and protein trafficking (brefeldin A). Additionally, the Ctx B subunit, alone, does not replicate these effects. RT-PCR and Western blot analyses indicate no significant increase in either the mRNA or protein expression for α-, β-, or, γ-ENaC subunits. Ctx increases the abundance of both β- and γ-ENaC in the apical membrane. Additionally, Ctx increases both phosphorylated and nonphosphorylated Nedd4-2 expression. These results demonstrate that human mammary epithelia express ENaC, which can account for the low Na+concentration in milk. Importantly, the results suggest that Ctx increases the expression but reduces the activity of the E3 ubiquitin ligase Nedd4-2, which would tend to reduce the ENaC retrieval and increase steady-state membrane residency. The results reveal a novel mechanism in human mammary gland epithelia by which Ctx regulates ENaC-mediated Na+transport, which may have inferences for epithelial ion transport regulation in other tissues throughout the body.

Maximum Output Power Control Using Short-Circuit Current and Open-Circuit Voltage of a Solar Panel

2012 ◽  
Vol 51 (10S) ◽  
pp. 10NF08 ◽  
Author(s):  
Takahiro Kato ◽  
Takuma Miyake ◽  
Daisuke Tashima ◽  
Tatsuya Sakoda ◽  
Masahisa Otsubo ◽  
...  
Keyword(s):  
Power Control ◽  
Output Power ◽  
Open Circuit Voltage ◽  
Short Circuit ◽  
Maximum Output Power ◽  
Short Circuit Current ◽  
Open Circuit ◽  
Solar Panel ◽  
Maximum Output

The Impact of Synchronous Distributed Generation (DG) on Distribution System

2015 ◽  
Vol 785 ◽  
pp. 388-392 ◽  
Author(s):  
Hasmaini Mohamad ◽  
Shahrani Shahbudin ◽  
Nofri Yenita Dahlan
Keyword(s):  
Distributed Generation ◽  
Distribution System ◽  
System Performance ◽  
Power Flow ◽  
Short Circuit ◽  
Short Circuit Current ◽  
Voltage Profile ◽  
Before And After ◽  
Potential Benefits ◽  
The Impact

Interconnection of Distributed Generation (DG) in distribution system presents many potential benefits as well as drawbacks. The impacts of DG might vary with the types of generator. This paper presents a study on the impacts of synchronous DG's interconnection in distribution system. Steady state analysis is carried out to analyze the impact of DG on voltage profile and short circuit current considering before and after DG interconnection. Dynamic analysis is also performed for investigating the performance of DG when a part of distribution system is being islanded. Results show that the penetration of DG contributes to the changes of power flow in the system, hence give impacts to the overall system performance.

scholarly journals Fault Assessment and Mitigation of the 132kV Transmission Line in Nigeria using Improved Resonant Fault Current Limiting (RFCL) Protection Scheme

2018 ◽  
Vol 3 (10) ◽  
pp. 38-44
Author(s):  
D. C. Idoniboyeobu ◽  
S. L. Braide ◽  
Wigwe Elsie Chioma
Keyword(s):  
Power System ◽  
Transmission Line ◽  
Short Circuit ◽  
Short Circuit Current ◽  
Resonant Circuit ◽  
Fault Current ◽  
Protection Scheme ◽  
Current Limiting ◽  
Simulation Results ◽  
The Impact

This research work proposed an improved Resonant Fault Current Limiting (RFCL) protection scheme to reduce the impact of three-phase short-circuit faults in a power system sub-transmission network. The model used an interpolator-extrapolator technique based on a Resonant Fault Current Limiter (RFCL) for automating the procedure of predicting the required reactor value that must be in resonant circuit to limit the short-circuit current values to permissible values. Using the developed model, short-circuit fault simulations on the three phases of the transmission line (Phase A-C) were performed in the MATLAB-SIMULINK environment. Simulation results were obtained by varying the resonant inductance (reactor) parameter of the RFCL circuit for each of the phases to obtain permissible short-circuit current levels and the values used to program a functional interpolator-extrapolator in MATLAB; the resonant values were typically set to values of inductance equal to 0.001H, 0.01H and from 0.1H to 0.5H in steps of 0.1H. Simulation results revealed the presence of very high short-circuit current levels at low values of the resonant inductor. From the results of simulations, there are indications that the RFCL approach is indeed very vital in the reduction of the short circuit current values during the fault and can safeguard the circuit breaker mechanism in the examined power system sub-transmission system. In addition, lower fault clearing times can be obtained at higher values of inductances; however, the clearance times start to converge at inductance values of 0.1H and above.

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