In this section, The basics of electromagnetic transients, HV Capacitors banks and their relations and functions in the power system are presented. Electromagnetic Transients (EMT) Electromagnetic transient (EMT) phenomena occurs in the power system when the network changes from one steady state into another which creates a disturbance in the power system that involve destructive high magnitudes of current and voltage or even both, as per (ANSI std. 1100-1992) the EMT is defined as “a sub-cycle disturbance in the AC waveform that is evidenced by a sharp brief discontinuity of the waveform. Transients may be of either polarity and may be of additive or subtractive energy to the nominal waveform”.[green wood][3] Transients can be generated …show more content…
Reduced system power losses. The capacitors are installed in a distribution system on pole-mounted racks, substation banks, and high voltage (HV) or extra-high voltage (EHV) units for bulk power applications. In industrial systems, the power factor correction capacitor units are utilized for group or individual loads. Capacitor unit are constructed in an enclosure (tank) and are designed to provide maintenance-free service. The major components of a capacitor includes electrodes, a dielectric material to separate the electrodes, a case, dielectric liquid, bushings , and a discharge resistor to discharge the capacitor when disconnected from the source. The capacitor banks are assembled from capacitor units connected in three-phase grounded-wye, ungrounded-wye, or delta configurations. The capacitor banks are either fixed or switched. Switched capacitors give added flexibility in the control of system voltage, power factor, and losses. Switched capacitors are usually applied with some type of automatic switched control. The control senses a particular condition. If the condition is within a pre-set level, the control's output level will initiate a close or trip signal to the switches that will either connect or disconnect the capacitor bank from the power
A Transient Ischemic Attack, generally referred to as a TIA, is a type of stroke that only last a few min...
On August 14th, 2003, a major blackout swept across portions of the northeastern United States and Canada. It was reported that a series of equipment outages in the Midwest led to uncontrolled cascading outages of power transmission lines and generators serving parts of the Northeast, Midwest and Canada. Automatic protective systems operated to open circuits and shut down power plants to prevent further spread of the outages. This is very similar to what happened in The Great Northeast Blackout of 1965. In both situations, the “grid system” shut down one generator in line at a time to protect a surge from the station before it.
Keefer, D. M. (2009, September 3). The Canadian Charger. Retrieved May 15, 2014, from The Canadian Charger: http://www.thecanadiancharger.com/page.php?id=5&a=115
The module AC/DC is directly related to the career path of the electrical linemen. In the module i learned about two types of electrical current, alternating (AC), and direct current (DC). In direct current (DC), the electric charge (current) only flows in one direction. Electric charge in alternating current (AC), on the other hand, changes direction periodically. The voltage in (AC) circuits also periodically reverses because the current changes direction. Electrical lineman work on power lines and other thing that have (AC) or (DC) current depending on what they are working on. Lineman work on electrically energized (live) and de-energized (dead) power line. They may perform a number of tasks associated with power lines, including installation or replacement of distribution equipment such as capacitor banks, distribution transformers on poles, insulators and fuses.
[4]. Lin, Y. L; Liu, C. W. & Chen, C. S. (2004). A new PMU-based fault detection/location technique for transmission lines with consideration of arcing fault discrimination— Part I: Theory and algorithms. IEEE Trans. Power Del., Vol. 19, No. 4, (October 2004), pp. 1587–1593.
The emergence of the Microgrids came after realizing that the architecture of the electricity grid existing nowadays (Figure 1) is getting obsolete, since it is based on the idea of a top-down system, which is predicated on unidirectional energy flows. [ASMUS09]
For the purpose of this assignment the experience of attending Electro-Convulsive Therapy will be discussed. It will include rationale for the procedure, an account of the procedure and the student nurses reflection on the experience using Gibbs’ model of reflection (Jasper 2003). Electroconvulsive therapy (ECT) is a medical treatment for severe mental illness in which a small, carefully controlled amount of electricity is introduced into the brain. This electrical stimulation, used in conjunction with anaesthesia and muscle relaxant medications, produces a mild generalised seizure or convulsion (Mankad et al 2010).
· B-phase transformer (EMTU-TT01) · Feedback electronic wattmeter · Multi-range moving-iron ammeter · Instrument voltage transformer THEORY AND INTRODUCTION ----------------------- Transformers are used all over the world to step-up and step-down electricity. The transformer is one of the most commonly used electrical devices. The reason the transformer is so popular is because they range in size from 240V to well over 240kV, stepping -up and stepping-down electricity all over the world.
Since early 2003 the Electrical Inspectorate has been working to raise public awareness of Residual Current Devices (RCDs), with the aim of eventually enforcing the use of these devices as recommended by the standard adopted by the St. Lucia Bureau of Standards for wiring of buildings SLNS/BS 7671: 2001- Requirements for Electrical Installations ¡V IEE Wiring Regulations ¡V Sixteenth Edition. These Regulations though only recently adopted by the Bureau of Standards is the Regulations referred to by the St. Lucia Electricity regulations of 1973 as the standard of wiring of buildings. For a very long time the cost of these devices had proven prohibitive for the enforcement of the requirement. However, it is now believed that safety concerns as it relates to electrical hazards such as fire and electrocution far outweigh the cost of these devices
For the prevantion of the electricity blackout we need to build smart power grid. A modernized electrical grid that uses analog or digital information and communications technology to gather and act on information, such as information about the behaviours of suppliers and consumers is known as a smart grid. This is used to improve the efficiency, reliability, economics, and sustainability of the production and distribution of electricity in an automated fashion[12]. The important aspects of smart grid is to electronic power conditioning and control of the production and distribution of
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.
Arthur Sharplin (1989), Lincoln Electric Company Harvard Case Study, retrieved from the link provided in the assignment post
Alternating current is always changing in direction and amplitude. The current flow in alternating current changes in even intervals. Ac usually changes in power and direction. The vast majority of power supplied for households and big business is alternating current. This is because of the ease of generating alternating current in alternators. The main concept of alternators is moving a conductor through magnetic lines. The change in the magnetic field around the conductor or vice versa makes electrons move. When you have physically moved either the conductor or magnet in a complete 306-degree circle you have produced one sine wave or one complete cycle. The amount of time it takes to complete one cycle is referred to as a period. The frequency of an alternating sine wave is the amount of cycles per second. Frequency is measured in hertz. One hertz is equivalent to one cycle per second. The frequency coming out of your electrical plug at home is 60 Hz. The peak value in a sine wave is the top voltage level away from zero. The peak-to-peak voltage value is referring to difference between the positive peaks value to the negative peak value. The effective or rms value of a sine wave is the actual amount you would use or measure using a multi-meter. In three-phase alternating current there are three different coils or conductors that produce three different sine waves.
As a graduate student, I will undertake research and coursework in Electrical Engineering to enhance my competencies in this field. I intend to complete my master's degree in order to pursue my doctorate. The research that I am most interested in pursuing at Northeastern University surrounds the optical properties of MEMS devices, and the development of substrate-based fast electro-optical interfaces. My interest in this area stems from my undergraduate study in MEMs development for tri-axial accelerometers.
Electrical Engineers research, develop, design, and test electronic components, products, and systems for commercial, industrial, medical, military, and scientific applications (Cosgrove 749). They are concerned with devices that use small amounts of electricity that make up electronic components such as integrated circuits and microprocessors. By applying principles and techniques of electronic engineering they design, develop, and manufacture products such as computers, telephones, radios, and stereo systems (EGOE, 121). Electrical engineers touch everyone lives through the things they have designed or created. Electrical engineers have invented the lights in your house, the television, the stereo, the telephone, computers, and even your doctor’s blood pressure gauge (Stine 300).