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…
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…
Line Protection Using Impedance (Distance) Relays
When a system has too many radial lines protection using time delay overcurrent relay becomes impractical. Time delay for relay…
Magnetic Circuit for Power Engineers
Terminology: Magnetic Flux: The total flow of a field is called its flux. Example total light emitted from a source…