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

Give the significance of sim and rim instruction, Give the significance of ...

Give the significance of SIM and RIM instruction available in 8085. Instruction SIM: Set Interrupt Mask. This is a 1 byte instruction and can be used three dissimilar functio

Integrator circuit, Q. Addition and integration can be combined by the summ...

Q. Addition and integration can be combined by the summing integrator circuit shown in Figure. With the given component values and input waveforms, sketch v o when S is opened at

Calomel electode, Explain the construction and working of Calomel electrode...

Explain the construction and working of Calomel electrode

The electrical circuit sign convention, The Electrical Circuit sign convent...

The Electrical Circuit sign convention Notice that current leaves a source at its high potential (positive) terminal but enters a load at its high potential (positive) ter

Explain the action of a pn-junction with bias, Q. Explain the action of a p...

Q. Explain the action of a pn-junction with bias. Consider both the forward bias and the reverse bias, and use sketches wherever possible.

Matlab, to design wheatstone bridge

to design wheatstone bridge

Single- and three-phase systems, Ac power has significant practical advanta...

Ac power has significant practical advantages over dc power in generation, transmission, and distribution. One major drawback of the single-phase circuit is the oscillatory nature

Effects of an increase in real national income, Q. What will be the...

Q. What will be the effects of an increase in real national income on the interest rate? Answer: An enhance in real national income will increase the interest rate. If

Derive the equations of the self bias circuit, Q. Derive the equations of t...

Q. Derive the equations of the self bias circuit? A circuit which is used to establish a stable operating point is the self biasing configuration. The circuit is shown in Fig

Develop an electric equivalent network, Q. For the mechanical spring-mass-f...

Q. For the mechanical spring-mass-friction system shown in Figure, the differential equation relating the force F(t) and the velocity u(t) is given by  where M is themass,D

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