Skip to main content

Lightning Phenomena

Lightning Phenomena

Lightning has always been attracting mankind since early times. Lightning is a natural electrical phenomenon consisting of a high current, short-time discharge that neutralizes an accumulation of charge in the atmosphere. The discharge path can be between two different locations in a cloud, two clouds, a cloud, and the earth (or any structure connected to the earth). The mechanisms by which such charge accumulations take place are not yet fully known but are related to the motions of large air masses that come across certain conditions of humidity, temperature, and pressure. When the electricity held becomes excessive a breakdown or lightning flash takes place. As explained earlier, lightning strokes that terminate on or near power lines create problems for power engineers. The real incentive to obtain additional knowledge about lightning came from the necessity of the electrical industry to protect against its effects. It has been proved that lightning is the greatest single cause of outages in the transmission sector. where the temperature is about -5°C and the main positive charge center is located several kilometers higher up, where the temperature is usually below -20°C. Figure (4.2) shows such a cloud located above an overhead transmission line.


Fields of about 1000 V/m exist near the center of a single bipolar cloud in which charges of about 20 C are separated by a distance of about 3 km, and indicate the total potential difference between the main charge centers to be between 100 and 1000 MV. The energy dissipated in a lightning flash is therefore of the order of 1000 to 10,000 M]. Vertical separation of the positive and negative charge centers is about 2-5 km, and the charges involved are 10-3 0C. During an average lightning storm, a total of the order of kilo-coulombs of charge would be generated between the 0°C and the -40° C and the -40°C levels, in a volume of about 50km.

Popular posts from this blog

RS Aggarwal Aptitude Book PDF Free Download

RS Aggarwal Aptitude Book PDF Free Download RS Agarwal Aptitude Book PDF Free Download: Quantitative Aptitude by R.S Aggarwal is a standout amongst the most inclining books among the hopefuls getting ready for Bank PO, PO, MBA, RBI, IBPS, CAT, SSC, IAS, PSC, Hotel Management, Railway Recruitment Exams, and other aggressive and placement tests. This book is suggested by different specialists in this field. This book covers relatively every theme which is being requested for the focused exams. On the off chance that you are looking to Download RS Aggarwal Quantitative Aptitude PDF's most recent version with the expectation of complimentary then you appear to be at the correct place.    Download PDF  RS Agarwal Aptitude Book PDF Free Download This book covers Problems on Surds and Indices, Simplification, Numbers and Ages, Pipes and Cisterns, Boats and Streams, Problems on Trains, Simple and Compound Interests, Time and Work, Permutations and Combination, Clocks, Odd Man Out, Heights

Comparison between VSI and CSI

Comparison between VSI and CSI In power electronic systems, inverters are an essential component that converts direct current (DC) into alternating current (AC). There are two main types of inverters used in power electronic systems: Voltage Source Inverters (VSI) and Current Source Inverters (CSI). Both have their own unique advantages and disadvantages, and the choice of which to use depends on the specific application and the desired outcome. Comparisons between voltage source inverters and current source inverters are as follows. In voltage source inverters, the input voltage is maintained constant and the amplitude of the output voltage does not depend on the load. However, the waveform of load current, as well as its magnitude, depends upon the nature of load impedance.  In current source inverters (CSI), the input current is constant but adjustable. The amplitude of output current from CSI is freelance of the load. However, the magnitude of output voltage and its undulation outp

Limitations of Terzaghi Theory

Limitations of Terzaghi Theory The value of the coefficient of consolidation has been assumed to be constant.  The distance d of the drainage path cannot be measured accurately in the field. The thickness of the deposit is generally variable, and an average value has to be estimated.  There is sometimes difficulty 1n locating the drainage face, and sometimes thin previous seams that can act as good drainage faces are missed in the boring operations. The equation is based on the assumption that the consolidation is one-dimensional. In the field, the consolidation is generally 3-dimensional. The lateral drainage may have a significant effect on the time rate of consolidation. The initial consolidation and secondary consolidation have been neglected. Sometimes these form an important part of the total consolidation. In actual practice, the pressure distribution may be far from linear or uniform.