n-channel JFET and p-channel JFET
Residual Current Circuit Breaker
Wien Bridge Oscillator
RC Phase Shift Oscillator
Selection of Materials Used for Electrical Contacts
Electrical Engineering and Technology
Welcome to this open and free electrical engineering study site. A strong team of well experienced electrical engineers in different fields of electrical technology has prepared this site for helping all people in the electrical community. The site covers entire aspects of the subject, from basic engineering to advanced and modern topics related to Electrical Engineering and Technology.
All articles of this site are totally based on practical experiences as well as a strong base of theoretical knowledge. The materials on this site are mainly concentrated on the field of electrical power systems but also cover all the basic electrical theories and definitions related to this part of engineering. This site is useful for all professionals dealing with electrical power transmission systems and electrical power distribution systems. It is also very very useful for those students who are studying for electrical engineering degrees or diploma courses at different colleges and universities. This site plays a vital role for getting extra knowledge beyond the text books. Materials on this site are written in very simple and understandable English. Information on this site can also be utilized as reference for different fields of electrical engineering and technology. Our study materials cover almost all the field of electrical power system engineering from basic to advanced.
So go through these electrical topics and get required knowledge for professional applications in electrical technology as well as for educational purposes. This is an absolutely free, open and online electrical power transmission and distribution reference cum guide book.
Electrical power systems includes power generation, electrical power transmission & distribution, control & power system protection, electrical switchgear, power transformers, control & protection relays, transmission & distribution substations, and all switch yard equipment. All the very basic electrical engineering theories related to this field of technology are also included in this study site.This site is continually improving and in the near future we will add many other functionalities to this website to make it a complete solution for electrical technology. Please give your suggestions to help make the site better. This is a complete reference of electrical engineering and technology.
This site covers many important topics related to different parts of power system engineering, like, basic electrical, electrical power transformer, electrical switchgear, power system protection, electrical power transmission system etc. The site provides many video presentations for different electrical theories to make your electrical engineering study more easy and understandable. In few words, it can be said that this site covers almost all topics related to electrical power system engineering and technology.
The most familiar form of energy in our daily lives is electrical energy. The branch of engineering which deals with producing, managing and utilizing this energy, is referred as electrical engineering. This field of engineering was introduced in an organized manner in the mid of 19th century. Electrical technology is not as old as civil and mechanical technologies. Interest in this field of study grew after the invention of electricity. It was June 1752 when Benjamin Franklin first tried to catch electricity from clouds during a heavy storm with the help of a flying kite. This was the beginning and to date still we are trying to manage this energy. Managing electrical energy (producing, transmitting, distributing, utilizing) is nothing but electrical engineering. Commercially this became an occupation only after 1950.
Electrical engineering is core engineering like civil and mechanical but it has a wide range of subfields. After modernization, many fields of engineering grew out of electrical such as electronics, computer, telecommunication engineering and much more. All the fields of study that directly or indirectly deal with electricity come under electrical engineering.
In a power generation plant where electrical energy is produced, the application of this engineering is huge. All the mechanical and as well as electrical equipment involved in producing electrical energy, such as alternators, boilers, turbines etc. are controlled and protected by electrical signals. All the relays and switches involved in operation of the equipment are either electromechanical or static electronics devices. In the modern age, these devices are digitally controlled by computer software. So in addition to core electrical engineering, these electrical engineering subfields (electronic, computer, software engineering and IT) are also involved in power generation.
When the voltage level of generated power is stepped up, electrical transformers are required. For proper control and protection of these transformers, a sophisticated switchgear system is required. Electrical switchgear includes all circuit breakers, electrical isolators, current transformers, potential transformers, control and protection relay system and many more. Modern electrical engineering deals with production, planning, operation, and maintenance of these systems.
After stepping up the electrical power, it is transmitted to a load center. Huge electrical technology is involved in electrical power transmission systems and networks including large national grids. The problems associated with these systems are solved by electrical engineering including all engineering subfields.
History of Electrical Engineering
Benjamin Franklin in 1752, was the first man who tried to utilize electricity from clouds by flying a kite during a stormy night. In 1780, Luigi Galvani was surprised when he saw that a dead frog’s leg twisted when it was touched by a silver and copper stick. He misunderstood the actual reason, thinking that the electricity came from the leg itself, and referred it as animal electricity. After development in 1800 by Alessandro Volta of the voltaic cell as a simple method of producing electricity from a chemical reaction, an actual revolution occurred in this field and the history of electrical engineering totally changed from this time.
It is needless to say that most of the theories, on which this field of engineering is built, are related to electromagnetism. The law of electromagnetism was invented by Michael Faraday in the year 1831. This law is popularly known as Faraday’s law of electromagnetic induction. The relation between current and voltage in a conductor was already stated by Georg Ohm, in 1827. This is Ohm’s law . Based on these two theories development of electrical technology began. In his experiment with electromagnetic induction, Michael Faraday designed the most basic model of an electrical rotating machine. In 1873, James Clerk Maxwell published his famous article on magnetism and electricity.
Werner von Siemens the founder of the German multinational engineering and electronic company Siemens, made great contributions in the early days of the history of electrical engineering. He was a great inventor and developer. Another great contributor to the electrical engineering was Sir Thomas Edison. We all know him as an inventor of the electric light bulb in the year 1879. This invention was a revolution. He was also the builder of the first electrical supply network in the world.
Although there were so many developments and research works going on before 1882, the study of electricity was not recognized as a separate field of engineering. In that year electrical engineering was introduced as a separate branch of engineering by TU Darmstadt University Germany. This was the beginning of studying electrical engineering as a professional degree. In that very year, Edison started the world’s first electric supply business at DC 110V. Initially, a total of 59 houses in Manhattan were connected to his network.
Although, alternating current had already been developed in Europe in the year 1850 by Guillaume Duchenne, it was not yet commercially distributed. George Westinghouse, an American entrepreneur, and engineer, finally came forward and financially supported the development of the AC power network. By the end of nineteenth century AC power transmission and distribution became popular and started dominating DC distribution systems.
After the development of the distribution network, electricity reached consumers. After electricity reaches the consumer, it is utilized for operating different equipment run by electricity. Electrical engineering is also involved in developing such industrial and domestic equipment at the consumer end. Many scientists and engineers involved themselves in inventing and developing such equipment. A new window had been opened in history of electrical engineering.
In 1895, Nikola Tesla transmitted radio frequency signal across a distance of eighty kilometers and developed radio transmitters. In 1897, the cathode ray tube was invented by Karl Ferdinand Braun and development of television technology began. In 1902, Willis Carrier developed air conditioning machines. In 1941, Konrad Zuse introduced the first form of programmable electromechanical computer. In 1943, Tommy Flowers produced the first prototype of a programmable digital computer. In 1946 Percy Spencer invented the microwave oven. Every day there are new inventions and developments in electrical engineering and technology. The discussion is far from over. Here, we tried to give an overview only.