Energy and Power
Characteristics of Lightning Strokes
Lightning, one of Mother Nature’s most spectacular events, started to appear significantly demystified after Franklin showed its electric nature with his famous electrical kite experiment in 1752. Although a great deal of research on lightning has been conducted since then,… Read more
Dec 19, 2010 | By Edvard Csanyi
High Voltage
Basics Of Subtransmission Systems
Subtransmission systems are those circuits that supply distribution substations. Several different subtransmission systems can supply distribution substations. Common subtransmission voltages include 34.5, 69, 115, and 138 kV. Higher voltage subtransmission lines can carry more power with less losses over greater… Read more
Dec 17, 2010 | By Edvard Csanyi
Maintenance
Maintenance for UPS systems
Maintenance of the UPS consists of preventive and corrective maintenance. Preventive maintenance consists of a scheduled list of activities. Performing these activities keeps the UPS in good working order and helps to prevent failures. Corrective maintenance is performed as a… Read more
Dec 16, 2010 | By Edvard Csanyi
Solar Power
Solar Power Tower
Solar power towers generate electric power from sunlight by focusing concentrated solar radiation on a tower mounted heat exchanger (receiver). The system uses hundreds to thousands of sun-tracking mirrors called heliostats to reflect the incident sunlight onto the receiver. These… Read more
Dec 15, 2010 | By Edvard Csanyi
Electric Motor
Keeping Motor Windings Dry
Special provision should be made to protect motor windings which operate in a damp atmosphere or are subject to condensation of moisture when out of service for long periods. Motors located in galleries of dams are frequently subject to continual… Read more
Dec 14, 2010 | By Edvard Csanyi
Low Voltage
Forms of Separation (2) – Fundamentals
In accordance with the Standard, separation of the various elements of an Assembly: busbars, functional units, terminals, can be claimed providing one or more of the following criteria are met: 1. “Protection against contact with live parts belonging to adjacent… Read more
Dec 13, 2010 | By Edvard Csanyi
Cables
Shielding Of Power Cables
Medium and high-voltage power cables, in circuits over 2000 volts, usually have a shield layer of copper or aluminum tape or conducting polymer. If an unshielded insulated cable is in contact with earth or a grounded object, the electrostatic field… Read more
Dec 12, 2010 | By Edvard Csanyi
Hydropower
Hydro vs. Wind vs. Solar Power?
Matthew Stein, author of When Technology Fails: A Manual for Self-Reliance, Sustainability, and Surviving the Long Emergency wrestles with that very question in his book. Here’s an excerpt: No single RE source works best all the time in all situations…. Read more
Dec 11, 2010 | By Edvard Csanyi
Energy and Power
Sources Of The Electric Energy – Generation
There are a number of ways to produce electricity, the most common commercial way being the use of a synchronous generator driven by a rotating turbine. The combination is called a turbine-generator. The most common types of turbine generators are… Read more
Dec 10, 2010 | By Edvard Csanyi
High Voltage
IEC 62271-200 – HV Switchgear And Controlgear
Part 200: AC metal-enclosed switchgear and controlgear for rated voltages above 1 kV and up to and including 52 kV Switchgears are important nodal points in modern power distribution. Correspondingly important is their reliable functioning, a clearly defined switching behavior… Read more
Dec 09, 2010 | By Edvard Csanyi
Energy and Power
Historical Review of Power System Stability Problems
As electric power systems have evolved over the last century, different forms of instability have emerged as being important during different periods. The methods of analysis and resolution of stability problems were influenced by the prevailing developments in computational tools,… Read more
Dec 08, 2010 | By Edvard Csanyi
Energy and Power
Time-Current Curves explained in details
Time-current curves are used to show how fast a breaker will trip at any magnitude of current. The following illustration shows how a time-current curve works. The figures along the bottom (horizontal axis) represent current in amperes. The figures along… Read more
Dec 07, 2010 | By Edvard Csanyi
Wind Power
Aerodynamics of Horizontal-Axis Wind Turbines
A wind turbine is a device for extracting kinetic energy from the wind. By removing some of its kinetic energy the wind must slow down but only that mass of air which passes through the rotor disc is affected. Assuming… Read more
Dec 06, 2010 | By Edvard Csanyi
Energy and Power
Economic advantages of power factor correction
Power supply authorities apply a tariff system which imposes penalties on the drawing of energy with a monthly average power factor lower than 0.9. The contracts applied are different from country to country and can vary also according to the… Read more
Dec 04, 2010 | By Edvard Csanyi
Low Voltage
Forms of Separation (1) – Introduction
Standard BS EN 60439 Part 1, describes a system for classifying the various forms of separation to be provided principally for: protection against contact with live parts belonging to the adjacent functional units. limitation of the probability of initiating arc… Read more
Dec 04, 2010 | By Edvard Csanyi
