Electrical Lectures
The choice of system voltage according to ANSI standard C84.1
The selection of system voltages is crucial to successful power system design. Reference lists the standard voltages for the United States and their ranges. The nominal voltages are given in Table 1 below. As can be seen, ANSI C84.1-1989 divides system… Read more
Aug 20, 2014 | By Edvard Csanyi
Energy Efficiency
An example of calculating the number of indoor lighting fixtures
These are the input data for the following calculation: An office area has length: 20 meter; width: 10 meter; height: 3 meter. The ceiling to desk height is 2 meters. The area is to be illuminated to a general level… Read more
Aug 18, 2014 | By Jignesh Parmar
Energy and Power
5 most common critical power distribution topologies
In many of today’s mission-critical applications, ever-increasing reliability requirements are the norm. A critical part of this reliability is the reliability of the electric power distribution system for a given facility. Among the most demanding applications is that of a… Read more
Aug 15, 2014 | By Edvard Csanyi
High Voltage
Main and Transfer (Inspection) Bus Arrangement commonly used in AIS
The main and transfer bus configuration connects all circuits between the main bus and a transfer bus (sometimes referred to as an inspection bus). Some arrangements include a bus tie breaker and others simply utilize switches for the tie between… Read more
Aug 13, 2014 | By Edvard Csanyi
Energy and Power
Methods Of Securing LV Circuit Breakers
Circuit breakers are typically secured in place by one of the following methods: Through bolts Bolted to the bus Stab locked to the bus or some type of receptacle connection Din rail mounted When a longer service life breaker is… Read more
Aug 11, 2014 | By Edvard Csanyi
Energy and Power
Methods Of Mounting LV Circuit Breakers
Methods used to mount circuit breakers can be divided into three general groups, those being: Fixed Removable (disconnectable unit), and Drawout (withdrawable) A review of these mounting methods follows. A circuit breaker that is bolted in its enclosure and wired… Read more
Aug 08, 2014 | By Edvard Csanyi
High Voltage
Analysing the costs of High Voltage Direct Current (HVDC) transmission
Introduction to HVDC Cost structure of HVDC Assumptions made in the price calculations Thyristor based HVDC system versus high voltage AC system VSC based HVDC system versus an AC system or a local generation source Comparative cost information It specifies… Read more
Aug 06, 2014 | By Edvard Csanyi
Energy and Power
7 most known high voltage insulation methods you should know
Before getting to the specifics of each material, there are a couple of issues that apply to all materials. First, it is important that the insulating material is homogeneous. This is to ensure that the dielectric constant is the same… Read more
Aug 04, 2014 | By Edvard Csanyi
Maintenance
Maintenance and inspection of the transformer bushings
There are six different inspections to be performed on the bushings of the power transformer: Routine inspection Regular inspection (Once every two years) Inspection due to excessive partial heatings Local damages inspection (fissures) on the bushings Inspection for oil leaks… Read more
Aug 01, 2014 | By Edvard Csanyi
Power Substation
Site selection considerations for the future power substation
At this stage, a footprint of the future power substation should be developed, including the layout of the major equipment. A decision on the final location of the facility can now be made and various options can be evaluated. Final grades,… Read more
Jul 30, 2014 | By Edvard Csanyi
Power Substation
Satellite communication for remote control and monitoring of substations
Substation Automation is a supervisory management and control system that lies in between transmission and distribution systems. The interests on substation automation have been increasing rapidly due to its numerous benefits to utilities. It has advanced further than a traditional… Read more
Jul 28, 2014 | By Edvard Csanyi
Cables
What engineers should know about using conduits in power substation designs
There are several locations where conduit is used in power substation designs. The most common one considered is conduit used to provide cable access to equipment, such as breakers, transformers, instrument transformers, and motor-operated disconnect switches located in the yard… Read more
Jul 25, 2014 | By Edvard Csanyi
High Voltage
An Example of Choosing 138 kV Line Circuit Breaker
To better understand a process of high voltage equipment selection, let’s discuss an example of choosing 138 kV Line #3 Circuit Breaker, shown in Figure 1, assuming that the following information about the system is available: The following information about… Read more
Jul 23, 2014 | By Edvard Csanyi
Testing and Commissioning
Testing of Power Transformer – Measurement of Zero-Sequence Impedance
The zero-sequence impedance is usually measured for all star-connected windings of the transformer. The measurement is carried out by supplying a current of rated frequency between the parallell connected phase terminals and the neutral terminal. The zero-sequence impedance per phase… Read more
Jul 21, 2014 | By Edvard Csanyi
Low Voltage
10 Important Precautions When Working On Low Voltage Energized Equipment
For most work, the electrical equipment must be de-energized because there is a high risk of injury to workers if they work on energized equipment. It may be possible to schedule such work outside of normal work hours to limit the inconvenience. Sometimes… Read more
Jul 18, 2014 | By Edvard Csanyi
