1. Transformer protection

Investigating differential relay characteristics (ANSI 87) and sizing current transformers for transformer differential protection

2. Relay code

code written in processing/ MATLAB to show the Relay ANSI numbers for protection in a power system

3. Motor analysis

motor starting methods compared, DOL and star delta (Y-D). Modelled the two starting methods on Etap software and exported motor currents as .xlsx and imported to MATLAB for data visualization and analysis.

analysis

DOL has a much higher peak current, causing more stress on electrical systems. Star-Delta takes longer to reach steady-state, but it significantly reduces inrush current. Energy consumption is lower in Star-Delta, making it more efficient for startup. The rate of change of current is much higher in DOL, which can cause voltage dips in the power system.