PARAMETERS THAT DETERMINE TRANSFORMER INRUSH CURRENT
High magnitude current lasting few power cycles during switching on a power transformer is known as transformer inrush current. Magnitude…
How Does Power Transformer Saturate?
Power transformer can saturate when voltage to frequency ratio for the particular transformer design is violated. Transformer is said to…
High Impedance Bus Differential Protection
High impedance bus differential is a method of differential bus protection using parallel set of current transformers (CT) from each…
Auto Recloser and Power Quality
What is a recloser? Recloser is an automatic self-controlled and self-contained device used by electric utility companies to disconnect power…
Bus Differential Fault-Waveform Analysis
In this article an actual fault waveform captured on high impedance bus differential relay at 13.2 kV is discussed. Fault…
How to select taps for multi ratio current transformer?
Multi ratio current transformers (CT) allow users to pick current transformation ratio needed for specific application from a given CT.…
Transformer Short Circuit Test
Short circuit test is performed on a transformer to measure the equivalent series resistance and reactance. Series resistance provides information…
Ground Potential Rise, Step and Touch Potential
Ground Potential Rise [GPR] Ground potential Rise (GPR) per IEEE Std 80 is defined as “The maximum electrical potential that…
What is KNAN / KNAF transformer?
KNAN is a transformer that uses less flammable non-mineral oil such as silicone oil, synthetic ester or natural ester (FR3)…
Types of Transformer Cooling
Power transformers can have different kVA depending on the type of cooling method used. Heat is one of the main…