3.1 State how eddy currents may be limited in the iron core of a transformer - NSC Electrical Technology Power Systems - Question 3 - 2016 - Paper 1

Both single-phase and three-phase transformers serve the same functional operations by stepping voltage up or down. Additionally, both can be designed as either closed core or shell core types.

1. Insufficient ventilation can hinder heat dissipation, leading to higher temperatures.
2. Constant overloading causes excessive current flow, which generates more heat than the transformer can handle.

1. Supply of three-phase and single-phase electricity to commercial sites.
2. Providing power to industrial areas requiring robust energy supply systems.

A transformer in a distribution network serves to adjust voltage levels to suitable values for transmission and utilization. It steps down high voltage from transmission lines to lower voltage suitable for end-users, ensuring efficiency and safety in electrical distribution.

Using the formula $V_{L} = V_{PH} \sqrt{3}$, the primary phase voltage can be calculated as follows:

$V_{PH} = \frac{V_{L}}{\sqrt{3}} = \frac{6600}{\sqrt{3}} \approx 3810.66 \text{ V}$

The secondary phase current $I_{PH}$ is the same as the line current in this case, so:

$I_{PH} = I_P = 30 ext{ A}$

The turns ratio ($N_p:N_s$) is calculated using:

$\frac{N_p}{N_s} = \frac{V_{P_{H}}}{V_{S_{H}}} = \frac{6600}{230} \approx 28.7$