Q1. A station supplies 250 kVA at a lagging power factor (p.f) of 0·8. A synchronous...

Q1. A station supplies 250 kVA at a lagging power factor (p.f) of 0·8. A synchronous motor is connected
in parallel with the load. If the combined load is 250 kW with a lagging p.f. of 0.9, determine :
(i) the leading kVAR taken by the motor.
(ii) kVA rating of the motor.
(iii) p.f. at which the motor operates.

Q2. A factory consists of the following
(i) An induction motor of 150 h.p with 0.7 p.f lagging and 80% efficiency.
(ii) A synchronous motor of 100 h.p with 0.85 p.f leading at 90% efficiency.
(iii) A lightning load of 50kW.
Find the annual electric charges if the tariff is Rs 100 per annum per kVA maximum demand plus 7
paise per kWh ; assuming the load to be steady throughout the year.

Expert Solution

please comment if u had any doubt

Manojponduru answered 2 years ago

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