A synchronous motor capable of operating with a leading power factor draws 15 kW from a distribution transformer while driving an air compressor. The remainder of the load on the transformer is 80 kW at 0.85 lagging power factor. (a) How many kilovars of capacitive reactive power must the synchronous motor produce to raise the overall power factor to 0.96 lagging? (b) What is the reactive factor of the synchronous motor operating in this manner?

A synchronous motor capable of operating with a leading power factor draws 15 kW from a distribution transformer while driving an air compressor. The remainder of the load on the transformer is 80 kW at 0.85 lagging power factor. (a) How many kilovars of capacitive reactive power must the synchronous motor produce to raise the overall power factor to 0.96 lagging? (b) What is the reactive factor of the synchronous motor operating in this manner?

Power System Analysis and Design (MindTap Course List)

6th Edition

ISBN:9781305632134

Author:J. Duncan Glover, Thomas Overbye, Mulukutla S. Sarma

Publisher:J. Duncan Glover, Thomas Overbye, Mulukutla S. Sarma

Chapter2: Fundamentals

Section: Chapter Questions

Problem 2.21P: An industrial plant consisting primarily of induction motor loads absorbs 500 kW at 0.6 power factor...

See similar textbooks

Similar questions

An infinite bus, which is a constant voltage source, is connected to the primary of the three-winding transformer of Problem 3.53. A 7.5-MVA,13.2-kV synchronous motor with a sub transient reactance of 0.2 per unit is connected to the transformer secondary. A5-MW,2.3-kV three-phase resistive load is connected to the tertiary Choosing a base of 66 kV and 15 MVA in the primary, draw the impedance diagram of the system showing per-unit impedances. Neglect transformer exciting current, phase shifts, and all resistances except the resistive load.
The total instantaneous power absorbed by a three-phase motor (under balanced steady-state conditions) as well as a balanced three-phase impedance load is (a) A constant (b) A function of time
The motors M1andM2 of Problem 3.45 have inputs of 120 and 60 MW, respectively, at 13.2 kV, and both operate at unity power factor. Determine the generator terminal voltage and voltage regulation of the line. Neglect transformer phase shifts.
Two alternators A and B are in parallel and supplying a 600-V,60 Hz bus load consisting of a 270 kVA unity power factor load a group of induction motors totaling 420 kVA at 89.4 percent power factor and a synchronous motor that draws 300kVA at 92.3 percent power factor leading. If the machine A is carrying 60 percent of the total active power load at a power factor of 70.4 percent lagging, determine the active and reactive components supplied by machine B.
A 400-V, 3-phase induction motor load takes 900 kVA at a power factor of 0.707. Calculate the KVA rating of the capacitor bank to raise the resultant power factor of the installation of 0.866 lagging. Find also the resultant power factor when the capacitors are in circuit and the motor load has fallen to 300 kVA at 0.5 power factor.
A single-phase alternator connected to 6,600-V bus-bars has a synchronous impedance of 10Ω and a resistance of 1 Ω. If its excitation is such that on open circuit the p.d. would be 5000 V, calculate the maximum load the machine can supply to the external circuit before dropping out of step and the corresponding armature current and p.f. [2864 kW, 787 A, 0.551]
Three of a 15 kVA, 2200:220 V, 50 Hz transformer are connected in ∆-∆ to supply at 220 Voltsline-to-line a three-phase induction motor load of 20 kVA. The power factor of the induction motor is0.85. The load is connected to the transformers by means of a common three-phase feeder whoseimpedance is 0,03+j0,06 Ω/phase. The transformers themselves are supplied from a constant-potentialsource by means of a three-phase feeder whose impedance is 2,5+j6,0 Ω/phase. The equivalentimpedance ((R''1+R2)+j(X''ℓ1+Xℓ2)) of one transformer referred to the low-potential side (secondary) is0,4+j0,5 Ω/phase. The magnetizing inductance and the resistance representing the core loss areneglected. Calculate the required source line voltage (Vs) if the load line voltage is 220 Volts.Hint: ZY = (1/3)Z∆
Two alternators rated 400 MW and 600 MW are operating in parallel. The droop characteristics of their governors are 3% and 4% respectively from no load to full load. Assuming that the alternators are operating at 50 Hz at no load, how would a load of 1000 MW be shared between them? What will be the system frequency at this load? [Ans. G1 = 468.132 MW, G2 = 531.669 MW, f= 48.296 Hz]
Question 1. a) What is the need of compensation in power system? b) Give the schematic diagram showing a shunt compensator on a distribution transformer. c) Give the desirable characteristic features f a shunt compensator. d) List different methods used in shunt compensator. e) Name two power factor correction method. f) Define Facts and name 2 series connected facts devices g Draw a circuit diagram of a Static Synchronous Series Compensator (SSSC) and gives his applications.
The power factor of a load of 400kW is 0.4 lagging. It is desired to improve this power factor to 0.7 lagging by using the over excited synchronous motor. If the synchronous motor takes 70 kW,find, 1.Power factor of synchronous motor 2.Leading kVAr of synchronous motor 3.kVA of synchronous motor.
In a Three-phase alternator, a given field current produces an armature current of 250 A on short-circuit and a generated e.m.f. of 1500 V on open-circuit. Calculate the terminal p.d. when a load of 250 A at 6.6 kV and 0.8 p.f. lagging is switched off. Calculate also the regulation of the alternator at the given load. Subject: Electrical engineering
The power factor of a load of 500 kW is 0.6 lagging. It is desired to improve this power factor to 0.9 lagging by using the over excited synchronous motor. If the synchronous motor takes 80 kW, find 1. Power factor of synchronous motor, 2. Leading KVAr of synchronous motor 3. KVA of synchronous motor