Protection
Delayed Auto-Reclosing On EHV Systems
On highly interconnected transmission systems, where the loss of a single line is unlikely to cause two sections of the system to drift apart significantly and lose synchronism, delayed auto-reclosing can be employed. Dead times of the order of 5s-60s are commonly used…. Read more
Aug 11, 2012 | By Edvard Csanyi
High Voltage
Primary Distribution Voltage Levels
Most distribution voltages are between 4 and 35 kV. In this article, unless otherwise specified, voltages are given as line-to-line voltages; this follows normal industry practice, but it is sometimes a source of confusion. The four major voltage classes are… Read more
Aug 10, 2012 | By Edvard Csanyi
High Voltage
The Structure Of Power System
An interconnected power system is a complex enterprise that may be subdivided into the following major subsystems: Generation Subsystem Transmission and Subtransmission Subsystem Distribution Subsystem Utilization Subsystem Generation subsystem includes generators and transformers. An essential component of power systems is… Read more
Aug 09, 2012 | By Edvard Csanyi
Energy and Power
Reliability of Compressed Air Energy Storage Plant
As the name implies, the compressed air energy storage (CAES) plant uses electricity to compress air which is stored in underground reservoirs. When electricity is needed, this compressed air is withdrawn, heated with gas or oil, and run through an expansion turbine… Read more
Aug 04, 2012 | By Edvard Csanyi
Cables
Types of Cable Installations in Electrical Network
There are a variety of ways to install power distribution cables. Each method ensures distribution of power with a unique degree of reliability, safety, economy, and quality for any specific set of conditions. These conditions include the electrical characteristics of… Read more
Jul 27, 2012 | By Edvard Csanyi
High Voltage
Autoreclosing in Transmission and Distribution Systems
Two main functions of Utility Electric System Operations department are Control and Protection. Control function deals with all operational aspects involved in efficient and optimal dispatching of available real power (with reactive power support) from the Generating units (and reactive… Read more
Jul 15, 2012 | By Edvard Csanyi
High Voltage
Transmission and Distibution Overhead Circuit Faults
Overhead (OH) Transmission circuits are usually HV level (110kV or 115kV and more) to EHV levels (230kV and beyond) and UHV levels (765kV and beyond). OH Distribution systems involve sub-transmission system circuits like 66kV down to 11kV….some times as low… Read more
Jul 11, 2012 | By Edvard Csanyi
High Voltage
FACTS – Flexible AC Transmission Systems
The acronym FACTS stands for “flexible AC transmission systems”. These systems add some of the virtues of DC, i.e., phase independence and fast controllability, to AC transmission by means of electronic controllers. Such controllers can be shunt or series connected… Read more
Jun 21, 2012 | By Edvard Csanyi
High Voltage
Reducing Distribution Line Losses
One of the main benefits of applying capacitors is that they can reduce distribution line losses. Losses come from current through the resistance of conductors. Some of that current transmits real power, but some flows to supply reactive power. Reactive… Read more
Jun 19, 2012 | By Edvard Csanyi
Transmission and Distribution
Sag and tension of transmission and distribution lines
The energized conductors of transmission and distribution lines must be placed to totally eliminate the possibility of injury to people. Overhead conductors, however, elongate with time, temperature, and tension, thereby changing their original positions after installation. Despite the effects of… Read more
Jun 17, 2012 | By Edvard Csanyi
Medium Voltage
Bus Switching Configurations In Air Insulated Substations (AIS)
Various factors affect the reliability of a substation, one of which is the arrangement of the switching devices. Arrangement of the switching devices will impact maintenance, protection, initial substation development, and cost. There are six types of substation bus switching… Read more
May 05, 2012 | By Edvard Csanyi
High Voltage
How HV transmission lines affects humans and plants?
By increasing population of the world, towns are expanding, many buildings construct near high voltage overhead power transmission lines. The increase of power demand has increased the need for transmitting huge amount of power over long distances. Large transmission lines… Read more
Mar 20, 2012 | By Jignesh Parmar
High Voltage
Using HVDC Technology For Transmitting Electricity
An alternate means of transmitting electricity is to use high-voltage direct current (HVDC) technology. As the name implies, HVDC uses direct current to transmit power. Direct current facilities are connected to HVAC systems by means of rectifiers, which convert alternating… Read more
Mar 05, 2012 | By Edvard Csanyi
Electrical Lectures
Types of neutral earthing in power distribution (part 2)
Resistance grounding has been used in three-phase industrial applications for many years and it resolves many of the problems associated with solidly grounded and ungrounded systems. Resistance Grounding Systems limits the phase-to-ground fault currents. Continued from Types of neutral earthing… Read more
Feb 09, 2012 | By Jignesh Parmar
Electrical Lectures
Types of neutral earthing in power distribution (part 1)
In the early power systems were mainly Neutral ungrounded due to the fact that the first ground fault did not require the tripping of the system. An unscheduled shutdown on the first ground fault was particularly undesirable for continuous process… Read more
Feb 06, 2012 | By Jignesh Parmar