One of the most complex disciplines in Electrical engineering is the Power System
Protection which requires not only the well understanding of the different components of power system and their behaviors but also the good knowledge and analysis of the abnormal circumstances and failures that can occur in any element of power system. Moreover, the rapid changing and development in relays principles as well as in their technologies are additional factors that oblige those people working in the field to expand and update continuously their knowledge. In this paper, we tried to shed light on the evolution of protective relays from the onset of the electrical energy to our days. We tried also to foresee the future prospects and trends in this area.
I. Introduction
Protective relaying is an integral part of any electrical power system. The fundamental objective of system protection is to quickly isolate a problem so that the unaffected portions of a system can continue to function. Protective relays are the decision-making device in the protection scheme [1]. These relay knew, through more than a century, an important change in their functionalities and technologies. Each change brings with their odds and improvement in both technical and financial aspects.
In this paper, we tried to shed light on the evolution of protective relays since the onset of the electrical energy to our days. We tried also to foresee the future prospects and trends in this area.
II. Historical background
Since the early days of the onset of electrical power the need of devices that allow to avoid the undesirable events in power system had been prescribed.
The history of protective relays refers to more than...
... middle of paper ...
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Electricity is an interesting subject. There is so much you can learn from it, like how our lights turn on or how we make cell phones. This is all a mystery until we finally get a little bit of information in our brains. I've just read two articles, "Energy Story" and "Conducting solutions". I also watched a video called Hands-on Science with Squishy circuits. I learned so much valuable information from these resources.
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Electricity and electrical components are a major part of our lives today. Our lives pretty much come to a halt if there is a power outage or if our electrical devices stop working, sometimes we even start panicking because we are so dependent on these components that we cannot afford to lose them and their importance and use only increases as time passes. We all use these electrical devices and also electricity itself but most of us do not think about the math and physics that works behind all of these things.
Technological and accidental hazards can be occur without warning and can be both hazardous material incidents and failures at nuclear power plant. In some cases, victims that have been exposed to harmful chemicals or radiation show little to no symptoms until several years later. There are an increasing number of new substances and chemicals being manufactured which has increased the likelihood of a hazardous material spill or release. This also increases the risk to the environment and to the health and safety of a community.
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Electrical engineering deals with electricity, electro-magnetism and electronics. It also covers power, control systems, telecommunications and signal processing. These engineers are usually concerned with large-scale electrical systems such as motor control and power transmission, as well as utilizing electricity to transmit energy. Electrical engineers may work on a diverse range of technologies, from the design of household appliances, lighting
Electricity has become a basic necessity for most people all over the world. We are depending on electricity for our everyday lives and if one day we did not have electricity we would have difficulty going through the day. I think we need to be more dependent on things that do not use electricity and only use electricity sometimes as a treat so just in case if one day electricity all goes away we could still live comfortably and still have a great life even without it.
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...g the Energy Revolution." Foreign Affairs. Nov/Dec 2010: 111. SIRS Issues Researcher. Web. 21 Nov 2011.