In: Electrical Engineering
4.11)The equivalent circuit parameters of a 150 kVA, 2400 V/ 240 V, 60 Hz transformer are as follows:
RHV = 0.21Ω, RLV = 2mΩ, XlHV = 0.45Ω, XlLV = 4.6mΩ, XmHV = 1.6kΩ, and RcHV = 12kΩ.
The transformer delivers to a load, rated current at a power factor of 0.85 lagging at rated voltage. Determine the input voltage, current, apparent power and power factor, (a) using the approximate equivalent circuit, and (b) not using the approximate equivalent circuit.
Problem 4.12 For the transformer in problem (4.11), determine the efficiency when operating with, 1. rated current, rated voltage and lagging power factor of 0.8, 2. 80% of rated current, rated voltage, and unity power factor. Problem
4.13 Calculate the voltage regulation of the transformer in problem (4.11) when delivering,
1. rated current at 0.9 lagging power factor,
2. rated current at unity power factor, and