Energy and Power
Bus Design In Aboveground Substations
Substations can be constructed partly or entirely within aboveground or belowground enclosures. However, cost is high and complexity is increased by fire-protection and heat-removal needs. The following discussion deals with exposed aboveground substations. The bus and associated substation equipment are… Read more
Jul 21, 2012 | By Edvard Csanyi
Energy and Power
Effect of Lightning Strike on Electrical Lines
The foregoing discussion concentrated on the principles of lightning strikes and how their effects can be mitigated. However, lightning strikes on electrical lines or substations are those that cause problems in the distribution network which come right into our residences… Read more
Jul 20, 2012 | By Edvard Csanyi
Electric Motor
AC Adjustable Speed Drive (ASD) – An Overview
The simplest and least expensive way to control the speed of a process or piece of equipment is to operate all the equipment at full speed. Many applications require the speed of a process or piece of equipment to be… Read more
Jul 19, 2012 | By Edvard Csanyi
Cables
Mark the ground with an X and say Dig Here!
No matter what method is used for fault locating on direct buried underground cable, at some point an “x” must be marked on the ground to say “dig here.” The most commonly used prelocation methods such as arc reflection or… Read more
Jul 18, 2012 | By Edvard Csanyi
High Voltage
Shunt Reactor Used In HV and EHV Systems
Main Power System parameters are System Voltages and Frequency which normally indicate the healthiness level (they indicate the level of Generated active and reactive Powers against the load power requirement). In a healthy system, Voltage and frequency are close to… Read more
Jul 17, 2012 | By Edvard Csanyi
Medium Voltage
Field Inspection of New Medium-Voltage Switchgear
Step Description of what you should do 1.1 Check switchgear assembly for alignment, levelness, and tightness of all bolting. 1.2 Check all equipment for the removal of blocking, supports, temporary ties, and temporary jumper wires. 1.3 Check control power transformer… Read more
Jul 16, 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
Electric Motor
Thermal (Overload) Motor Relay Protection
The majority of winding failures in motor are either indirectly or directly caused by overloading (either prolonged or cyclic), operation on unbalanced supply voltage, or single phasing, which all lead through excessive heating to the deterioration of the winding insulation… Read more
Jul 14, 2012 | By Edvard Csanyi
Cables
Locating underground electrical cable faults
Before attempting to locate underground cable faults on direct buried primary cable, it is necessary to know where the cable is located and what route it takes. If the fault is on secondary cable, knowing the exact route is even… Read more
Jul 13, 2012 | By Edvard Csanyi
Energy and Power
Definitions from the Standard UL 489 (MCCB)
The requirements of this standard cover molded-case circuit breakers (MCCB), circuit breaker and ground-fault circuit-interrupters, fused circuit breakers, and accessory high-fault protectors. These circuit breakers are specifically intended to provide service entrance, feeder, and branch circuit protection in accordance with… Read more
Jul 12, 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
Energy and Power
Delta-Star Transformer Connection Overview
The Delta-Star transformer connection is utilized to increase voltage levels and is frequently applied at the end or beginning of high-tension power transmission systems. The primary is configured in a delta arrangement, while the secondary is arranged in a star… Read more
Jul 10, 2012 | By Jignesh Parmar
Energy and Power
The Role of Circuit Breakers in LV/MV Power Systems
A circuit breaker is protective device which is designed to automatically open an electrical circuit thus preventing harm and damages to equipment and personnel. The damages are due to over load, short circuits and sometimes earth faults. Circuit breakers are made… Read more
Jul 09, 2012 | By Edvard Csanyi
Electrical Lectures
Fundamental Concepts of Insulation Testing
Probably 80% of all testing performed in electrical power systems is related to the verification of insulation quality. This technical article briefly describes the fundamental concepts of insulation testing including – insulation behavior, types of tests, and some test procedures…. Read more
Jul 07, 2012 | By Edvard Csanyi
Energy and Power
Delta-Delta Transformer Connection Overview
In this type of connection, both the three phase primary and secondary windings are connected in delta as shown in the Figure 1: The voltages on primary and secondary sides can be shown on the phasor diagram (Figure 2): This… Read more
Jul 06, 2012 | By Jignesh Parmar
