Question

A three phase diode rectifier has an input voltage of 480 V (line-to-line) at 50 Hz. It is connected to a load with resistance R=25Ω and inductance L = 50 mH. The apparent power flowing from source to load is (Consider negligible ripple content in output).

A. 12.28 kVA
B. 39.60 kVA
C. 17.60 kVA
D. 28.90 kVA

Answer 1

The apparent power flowing from the source to the load in a three-phase diode rectifier can be calculated using RMS values of the voltage and current. By substituting the given values into the formulas, the apparent power is approximately 12.28 kVA.

Step-by-step explanation:

To find the apparent power flowing from the source to the load, we need to calculate the root mean square (RMS) values of the voltage and current. In a three-phase diode rectifier, the RMS voltage is given by:

VRMS = Vpeak / √(2)

Given that the input voltage is 480 V (line-to-line), the peak voltage can be found using the formula:

Vpeak = VRMS * √(2)

Substituting the values, we get:

Vpeak = 480 * √(2)

To find the RMS current, we can use Ohm's Law:

IRMS = VRMS / R

Substituting the given resistance value of 25 Ω, we get:

IRMS = VRMS / 25

The apparent power is then given by:

Apparent Power = VRMS * IRMS

Calculating the values and substituting them into the formula, the apparent power is approximately 12.28 kVA.