Category: Power Systems
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SF6 Circuit Breakers: Features, Operation & Applications
Introduction Many modern designs of circuit breakers for use at transmission voltages utilize sulphur hexafluoride (SF6) gas both as an arc-interrupting/arc-quenching and a dielectric medium. At distribution voltages SF6 designs of circuit breakers are also used, however vacuum and bulk-oil circuit breakers still find a wide use as alternatives. The SF6 is an electron-negative gas…
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5 Causes of High-Voltage Switchgear Failures
Switchgear is basically equipment used switch ON or OFF generators, transmission lines, distributors and other equipment under both normal and abnormal conditions. Switchgear consists of switching and protecting devices such as switches, fuses, circuit breakers, relays, and so forth. In other words switchgear can be defined as equipment used for switching, controlling and protecting the…
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Main Types of Earthing Systems
Introduction The process of connecting the metallic frame i.e. non-current part of electrical equipment or some electrical part of the system such as the neutral point of the secondary side of the distribution transformers or the star point in a star connected system to the earth is called grounding or earthing. The potential of the…
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DC Transmission and Distribution
In most cases, the dc power is obtained from large ac power systems by employing converting mechanisms like synchronous or rotary converters, solid-state converters and motor-generator sets and so forth. The reasons why power generation is done in ac form rather than dc are: How DC Power is Obtained from AC Power A general layout…
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Major Technologies for Smart Grid Implementation
Smart grid can enhance legacy electric systems (i.e. the traditional electricity infrastructure) by improving reliability and security; additional smart grid can offer economic benefits and cost savings, environmental improvement, and so forth. Generally smart grid represents the integration of digital technologies, sensors and other information and communication technologies to enable more efficient and reliable electricity…
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4 Common Arrangements of Distribution Substations
The general technique of supplying large quantity of power to factories or other complexes is by means of high-voltage (HV) supply, typically at 11 kV, occasionally at 6.6 kV. The installation consists of a main substation at the point of entry, with HV cables to supply subsidiary substations located near load centres. Where necessary, it…
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AC Transmission and Distribution Systems
Electrical energy is generated, transmitted and distributed in the form of AC. Since, alternating voltage can be changed in magnitude by means of a transformer; it is possible to transmit AC power at high voltage which reduces the current in the conductors hence the line losses. The conductors system is the means by which electric…
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Miniature Circuit Breakers (MCBs)
Miniature circuit breakers (MCBs) are electromechanical devices that protect an electrical circuit from over currents, in other words, MCBs are switches that automatically turns OFF when the current flowing them exceeds the maximum allowable limit. Over currents in an electrical circuit may be caused by short circuits overload or faulty designs. MCBs functions by interrupting…
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Overhead vs. Underground Power Distribution Systems
A power distribution system is the electrical system between the sub-station fed by the transmission system and the consumer’s meters. A distribution system generally is made up of feeders, distributors and the service mains. In this case, a feeder is a conductor which connects the substation (localized generating station) to the area where the power…
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Advantages of Fluid Power over Electric Power Systems
Generally fluid power systems tend to be insufficient, requiring much more energy input to the fluid than what is extracted at the points of use. When large amounts of energy need to be transmitted over long distances, electricity is a more practical medium for the task. Nonetheless, fluid power systems have certain advantages over electric…