Electrical Engineer

  Nowadays, SCRs are available of ratings up to 10 KV and 3 KA. But sometimes we face demand, more than these ratings. In this case combination of more than one SCRs is used. Series connection of SCRs meets high voltage demand and parallel connection of SCRs meets high current demand. These series and parallel connection of SCR or Thyristor will work efficiently if all SCRs are fully utilized. Although all SCRs in a string are of same rating, their V-I characteristics differ from one another. This leads to unequal voltage or current division among them. Hence every SCR is not fully utilized. So the efficiency of string is always less than 100% according to the given expression With increase in the numbers of SCRs in a string voltage or current handled by each SCR is minimized. This phenomenon increases the reliability of the string, but reduces the utilization of each SCR. Thus string efficiency decreases. Reliability of string is measured by derating factor (DRF) which is given b

  Solar Cell: Working Principle & Construction (Diagrams Included) What is a Solar Cell? A solar cell (also known as a photovoltaic cell or PV cell) is defined as an electrical device that converts light energy into electrical energy through the photovoltaic effect . A solar cell is basically a p-n junction diode . Solar cells are a form of photoelectric cell, defined as a device whose electrical characteristics – such as current , voltage , or resistance – vary when exposed to light. Individual solar cells can be combined to form modules commonly known as solar panels. The common single-junction silicon solar cell can produce a maximum open-circuit voltage of approximately 0.5 to 0.6 volts. By itself this isn’t much – but remember these solar cells are tiny. When combined into a large solar panel, considerable amounts of renewable energy can be generated. Construction of Solar Cell A solar cell is basically a junction diode , although its construction is little bit different fr