Page 204 - Basic Electrical Engineering

Figure 2.120

Current through the circuit,

2
Power transferred or consumed = I R L

Transfer Efficiency,

Percent Efficiency = 50 per cent.

2.9 STAR–DELTA TRANSFORMATION
Electrical network problems can be simplified by converting three resistances

forming a delta to corresponding three resistances forming an equivalent star
between the three terminals of the network. Similarly, resistances in the star

formation can be converted into equivalent delta. Let us take a simple
example as in Fig. 2.121 (a). Suppose we want to calculate the current

supplied by the voltage source to the network. As such we have to write the
equations for the three loops using Kirchhoff’s laws and solve these

equations to find the total current supplied by the battery. However, simply
by transformation of three resistances in delta to three resistances forming an