Calculate the maximum motor torque, Electrical Engineering

Assignment Help:

A 1000-hp, 2300-V, wye-connected, three-phase, 60-Hz, 20-pole synchronous motor, for which cylindrical-rotor theory can be used and all losses can be neglected, has a synchronous reactance of 5.00 /phase.

(a) The motor is operated from an infinite bus supplying rated voltage and rated frequency, and its field excitation is adjusted so that the power factor is unity when the shaft load is such as to require an input of 750 kW. Compute the maximum torque that the motor can deliver, given that the shaft load is increased slowly with the field excitation held constant.

(b) Instead of an infinite bus as in part (a), let the power to the motor be supplied by a 1000-kVA, 2300-V, wye-connected, three-phase, 60-Hz synchronous generator whose synchronous reactance is also 5.00/phase.The generator is driven at rated speed, and the field excitations of the generator andmotor are adjusted so that themotor absorbs 750 kW at unity power factor and rated terminal voltage. If the field excitations of both machines are then held constant, and the mechanical load on the synchronous motor is gradually increased, compute the maximum motor torque under the conditions. Also determine the armature current, terminal voltage, and power factor at the terminals corresponding to this maximum load.

(c) Calculate the maximum motor torque if, instead of remaining constant as in part (b), the field currents of the generator and motor are gradually increased so as to always maintain rated terminal voltage and unity power factor while the shaft load is increased.


Related Discussions:- Calculate the maximum motor torque

Cro, role of trigger circuit in cro

role of trigger circuit in cro

What are the modes used in display modes, What are the modes used in displa...

What are the modes used in display modes? 1. Left Entry mode In the left entry mode, the data is going into from the left side of the display unit. 2. Right Entry Mode

Sensor selection, Submit a brief report on the selection of two commerciall...

Submit a brief report on the selection of two commercially available sensors for the following: • Research and recommend a sensor for a real full size conveyor system of approxima

Matlab simulation, Simulate and compare BER of QPSK system and 4-QAM system...

Simulate and compare BER of QPSK system and 4-QAM system without grey coding Eb/No=0.2.4.6.8.10

Prove modified algorithm better than the elevator algorithm, A slight modif...

A slight modification of the elevator algorithm for scheduling disk requests is to always scan in the same direction, In what respect is this modified algorithm better than the ele

Explain from the drain characteristics, Q. Explain from the drain character...

Q. Explain from the drain characteristics that a JFET has  infinite resistance? When V GS = 0v when a positive voltage Vds has been applied across the channel and the gate

Find v and i , Find V and I in the figure given below using ideal diode mod...

Find V and I in the figure given below using ideal diode model

Write Your Message!

Captcha
Free Assignment Quote

Assured A++ Grade

Get guaranteed satisfaction & time on delivery in every assignment order you paid with us! We ensure premium quality solution document along with free turntin report!

All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd