The scope of this paper is to describe a real electrical installation of renewable energy using photovoltaic cells. The displayed power grid connected network was established in 2007 at area of Northern Greece. The photovoltaic park is composed of 6120 photovoltaic cells able to deliver a total power of 1.101.600 Wp. For the transformation of DC voltage to AC voltage have been used 25 stand alo...

Surge protective device is a part of internal lightning protection and it crucially to divert the certain amount of surges to the ground before the protected load able to handle. Therefore, this paper studying the enhancement of SPD through the effect of adding a filter in hybrid surge protection circuit using simulation modeling. Ordinarily, filter is used as in eliminating noises in certain a...

1 Abstract— Nowadays, power systems are characterized with heavy loading conditions, abrupt changes in generation patterns, extensive switching of power system configuration and high penetration of distributed generation (DG). Under those conditions performance of the conventional relays that rely on predefined settings may deteriorate leading to system wide disturbances and blackouts. To ensur...

OBJECTIVE To educate athletic trainers and others about the dangers of lightning, provide lightning-safety guidelines, define safe structures and locations, and advocate prehospital care for lightning-strike victims. BACKGROUND Lightning may be the most frequently encountered severe-storm hazard endangering physically active people each year. Millions of lightning flashes strike the ground an...

Using FORTE photodiode detector (PDD) observations of lightning, we have determined the geographic distribution of nighttime flash rate density. We estimate the PDD flash detection efficiency to be 62% for total lightning through comparison to lightning observations by the TRMM satellite’s Lightning Imaging Sensor (LIS), using cases in which FORTE and TRMM viewed the same storm. We present here...

[1] Seasonal variations on lightning activity of precipitation systems over south China and Taiwan before and after the onset of Mei‐Yu have been observed by the lightning imager sensor (LIS) on board the Tropical Rainfall Measuring Mission (TRMM) satellite. Lightning storms before Mei‐Yu onset show higher probability of lightning, higher flash rate, and larger radar reflectivity in the mixed‐p...

A new method to calculate lightning fatality risk is presented in order to develop a way to identify the lightning risk in areas where lightning fatality data are not available. This new method uses GIS software to multiply lightning flash density and population density on a grid and display the results on a map. A comparison to the known lightning fatality data was done to verify the method. T...

This paper presents a technique for electromagnetic field analysis on surge response due to Mid-span back-flashovers effects in lightning protection system of 500 kV EHV single circuit transmission tower by the neural networks method. These analyses are based on modeling lightning return stroke as well as on coupling the electromagnetic fields of the stroke channel to the line. The ground condu...

Power system overvoltages due to switching, lightning and other disturbances are the main problem for designers of the power transformers. Once some frequencies of the incoming surges match with some of the natural frequencies of transformer winding, the resonance phenomenon is expected in transformer winding. The resonant overvoltages may destroy the insulation between turns and cause to insul...