Calculate the input reactive power of the motor after pf

Question

Problem: In order the power factor of a 3.3kV, 50Hz, 3-phase star connected induction motor to 0.9 lagging, it is found that the required capacitance per phase for a capacitor bank connected in star across the motor is 45.59 µF. the motor is 85% efficient and delivers a full load power output of 500kW.

a. Calculate the input reactive power of the motor after p.f. improvement.

b. Calculate the capacitive reactance per phase of the capacitors connected in star across the motor.

c. Calculate the line current and the reactive power of the capacitors bank.

d. Calculate the values of input reactive power and the power factor before p.f. improvement.

e. Calculate the capacitance per phase required to give the same power factor improvement if the capacitors were connected in DELTA across the motor.

f. State the importance of power factor improvement to industry.

Answer 1

Consider the case situation provided regarding electrical engineering and after that you have to write answer for all parts by applying the suitable formulas. Question: In order, the power factor of a 3.3kV, 50Hz, 3-phase star joined induction motor to 0.9 lagging, it is found that the required capacitance per phase for the capacitor bank joined in star across the motor is 45.59 µF. the motor is 85% efficient and delivers a full load power output of 500kW. a) Compute the input reactive power of motor after p.f. improvement. b) Compute the capacitive reactance per phase of the capacitors joined in star across the motor. c) Compute the line current and the reactive power of the capacitors bank. d) Compute the values of input reactive power and the power factor by p.f. improvement. e) Compute the capacitance per phase needed to provide similar power factor improvement if the capacitors were joined in DELTA across motor.