Protection
Bus protection – Overcurrent differential
When selecting relays for bus protection, a major concern is the ability of the protective relaying scheme to restrain from tripping for close-in line faults. Tripping for bus faults, the reason for installing bus differential relaying, is less of a… Read more
Aug 31, 2011 | By Edvard Csanyi
Energy and Power
How reactive power is helpful to maintain a healthy system
We always tend to reduce reactive power to improve system efficiency. This is acceptable at some level. If the system is purely resistive or capacitance, it may cause problems in the Electrical system. AC systems supply or consume two kinds… Read more
Aug 29, 2011 | By Jignesh Parmar
Power Substation
Difference between Power Transformer and Distribution Transformer
Power transformers are used in transmission network of higher voltages for step-up and step down application (400 kV, 200 kV, 110 kV, 66 kV, 33kV) and are generally rated above 200MVA. Distribution transformers are used for lower voltage distribution networks… Read more
Aug 27, 2011 | By Jignesh Parmar
Energy and Power
Surge arrester types and auxiliary equipment
Nearly 100 years ago, electrode gaps (rod, sphere, or pipe) were used to limit overvoltages on equipment (Sakshaug, 1991). Some of these systems, particularly pipe gaps, may still be in service today. However, the characteristic of gap sparkover voltage vs…. Read more
Aug 25, 2011 | By Edvard Csanyi
Energy and Power
How to save electrical energy at home
In our home we use lot of electrical equipment like TV, Freeze, Washing machine, Mp3 player, music system, computer laptop. But we have not adequate knowledge for how to use this electrical equipment in proper way. Due to this ignorance… Read more
Aug 23, 2011 | By Jignesh Parmar
High Voltage
Capacitor protection by surge arresters – ABB
Generally speaking, capacitor protection by surge arresters has been a difficult task before ZnO arresters became available. The high discharge currents and possible energies associated with an arrester operation at a capacitor bank heavily stressed the spark gaps in a… Read more
Aug 22, 2011 | By Edvard Csanyi
Energy and Power
Autotransformers in few words
It is possible to obtain transformer action by means of a single coil, provided that there is a “tap connection” somewhere along the winding. Transformers having only one winding are called autotransformers, shown schematically in figure 1. An autotransformer has… Read more
Aug 19, 2011 | By Edvard Csanyi
Industrial Automation
How Stuxnet (PLC virus) spreads – Part 4
Continued from How Stuxnet (PLC virus) spreads – Part 3 » Read here Once the worm has a foothold in the Perimeter Network, it would attempt to infect any print servers and file servers it could discover. Next, the worm… Read more
Aug 18, 2011 | By Edvard Csanyi
High Voltage
Budgeting and Financing Substation
The construction of new substations and the expansion of existing facilities are commonplace projects in electric utilities. However, due to the complexity, very few utility employees are familiar with the complete process that allows these projects to be successfully completed…. Read more
Aug 16, 2011 | By Edvard Csanyi
Energy and Power
Applications and forms of differential relays
Differential relays take a variety of forms, depending on the equipment they protect. The definition of such a relay is “one that operates when the vector difference of two or more similar electrical quantities exceeds a predetermined amount. It will… Read more
Aug 15, 2011 | By Edvard Csanyi
Geothermal Energy
New download – Geothermal Electricity Basics
Geothermal electricity is electricity generated from geothermal energy. Technologies in use include dry steam power plants, flash steam power plants and binary cycle power plants. Geothermal electricity generation is currently used in 24 countries while geothermal heating is in use… Read more
Aug 14, 2011 | By Edvard Csanyi
Energy and Power
Whole-House Protection Strategy
No single SPD (Surge Protection Strategy) can protect all the equipment in a residence from all causes of electrical surges. Instead, a whole-house protection strategy, consisting of point-of-entry and point-of-use SPDs, is necessary to help guard against disturbances from inside… Read more
Aug 13, 2011 | By Edvard Csanyi
Electronics
Resistors in detail
Resistors are one of the simplest varieties of electronic components. A resistor is a two-terminal device that has a fixed relationship between the current passing through the device and the voltage drop across the device. This relationship is described in… Read more
Aug 12, 2011 | By elaina
Hydropower
Arrangement of Hydropower Plants
Hydropower machine is the designation used for a machine that directly convert the hydraulic power in a water fall to mechanical power on the machine shaft. This power conversion involves losses that arise partly in the machine itself and partly… Read more
Aug 10, 2011 | By Edvard Csanyi
Electric Motor
Cooling and Ventilation of Electric Motors (IC)
All rotating electrical machines generate heat as a result of the electrical and mechanical losses inside the machine. Losses are high during starting or dynamic braking. Also, losses usually increase with increased loading. Cooling is necessary to continuously transfer the… Read more
Aug 08, 2011 | By Edvard Csanyi
