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1. Fig. Pl is an equivalent circuit for a $1200 / 120 \mathrm{~V}, 60 \mathrm{~...

Sep 6, 2024

Key Concept

Transformer losses include iron loss (core loss) and copper loss (winding loss).

Explanation

Iron loss is primarily due to hysteresis and eddy currents in the transformer core, while copper loss is due to the resistance of the windings when current flows through them. The efficiency of a transformer can be calculated by considering these losses.

Key Concept

Copper loss is calculated using the formula

P_{cu} = I^2 R

, where

I

is the current through the windings and

R

is the resistance.

Explanation

To estimate copper loss, you need to determine the current flowing through the primary and secondary windings and apply the formula for copper loss. This loss is significant when the transformer is under load.

Key Concept

The exciting current

I_{e}

is the current required to magnetize the transformer core.

Explanation

This current is typically small compared to the load current and can be estimated based on the transformer's rated voltage and power factor. It is essential for maintaining the magnetic field in the core.

Key Concept

The efficiency of a transformer is given by the formula

\eta = \frac{P_{out}}{P_{in}} \times 100\%

, where

P_{out}

is the output power and

P_{in}

is the input power.

Explanation

Efficiency can be calculated by considering the output power minus the losses (iron and copper) and comparing it to the input power. A higher efficiency indicates a better-performing transformer.