A factory load may be represented by a series combination of a resistor and an…
PHYSICS · Subjective · CBSE · Physics · Alternating Current · Alternating Current
Problem
A factory load may be represented by a series combination of a resistor R0=60Ω and an inductor of inductive reactance XL=80Ω at the supply frequency. The load is operated from a 415 V, 50 Hz single-phase mains.
(i) Calculate the initial current drawn from the mains and the initial power factor of the load.
(ii) The management wishes to raise the power factor to 0.9 lagging without altering the current magnitude appreciably. Determine the value of an additional pure resistor that must be connected in series with the existing load to achieve the desired power factor.
(iii) After installing the additional resistor, compute the new current and the average power supplied to the load.
(iv) State one disadvantage of using resistive power-factor correction as compared to capacitive compensation.