Energy and Power

Energy and Power

## How to identify these 4 parameters and lower facility’s electricity bill

Testing and Commissioning

Protection

# How to determine power transformer impedance for calculation of short-circuit currents

In order to calculate short-circuit currents, it is obligatory to know conductor-specific equivalent data and impedances of electrical operational equipment, which are usually given by the respective manufacturer. The calculation…...

Jan 25, 2019 | Edvard

# 6 not-that-easy-to-understand terms related to a power transformer you should understand

There are many terms related to the power transformer operation that can be easily visualized which are especially important for students, like for example transformer construction or regular working principle…. Read more

Jan 21, 2019 | Edvard

# The basic understanding of an earthing protection system (diagram and definitions)

As you already know, protective conductors are the main part of every earthing protection system, but the complexity of the system will increase with the requirements of information technology, voltage… Read more

Jan 16, 2019 | Edvard

# The basic things about substations you MUST know in the middle of the night!

To explain in very simple words, I would say that substation is a bunch of electrical devices gathered and connected in one place. On top are clever electrical devices who… Read more

Jan 09, 2019 | Edvard

# The Essentials Of Current Transformers In Power Circuits (Theory and Practice)

If the voltage or current in a power circuit are too high to connect measuring instruments or relays directly, coupling is made through transformers. Such measuring transformers are required to… Read more

Dec 03, 2018 | Edvard

# What is polarity and why it’s important for transformers and protection relays

Polarity is very important for the operation of transformers and protection equipment. A clear understanding of polarity is useful in understanding and analyzing of transformer connections and operation as well… Read more

Nov 19, 2018 | Edvard

# Power transformer protection relaying (combined differential & restricted earth fault)

In previous article we described how overcurrent, restricted earth fault (REF) and differential protection of a transformer can be applied and explained their schemes. This part continues with other, also… Read more

Nov 14, 2018 | Edvard

# Power transformer protection relaying (overcurrent, restricted earth fault & differential)

The problems relating to transformer temperature rise above an assumed maximum ambient temperature require some means of protection. Let’s summarize the problems and the possible forms of transformer protection that… Read more

Nov 12, 2018 | Edvard

# Biased-differential protection theory and application

The term biased-differential or percentage differential is based on the fact that the operating threshold increases with the through current. Because of that, comparison of upstream and downstream currents in… Read more

Oct 22, 2018 | Edvard

# Lecture Notes In DC Electric Sources and Principles Of Electrical Circuits

DC sources refer to sources of electrical energy which are associated with constant voltages and currents. A DC power supply can be constructed as an electronic circuit operating from the… Read more

May 16, 2018 | Edvard