Explain about direct-current machines, Electrical Engineering

Assignment Help:

Q. Explain about Direct-current machines?

Generally speaking, conventional dc generators are becoming obsolete and increasingly often are being replaced by solid-state rectifiers in most applications for which an ac supply is available. The same is not true for dc motors. The torque-speed characteristics of dc motors are what makes them extremely valuable in many industrial applications. The significant features of the dc drives include adjustable motor speed over wide ranges, constant mechanical power output or torque, rapid acceleration or deceleration, and responsiveness to feedback signals.

The dc commutator machines are built in a wide range of sizes, from small control devices with a 1-W power rating up to the enormous motors of 10,000 hp or more used in rolling-mill applications. The dcmachines today are principally applied as industrial drivemotors, particularly when high degrees of flexibility in controlling speed and torque are required. Such motors are used in steel and aluminumrollingmills, tractionmotors, overhead cranes, forklift trucks, electric trains, and golf carts.Commutatormachines are also used in portable tools supplied frombatteries, in automobiles as starter motors, in blower motors, and in control applications as actuators and speed-sensing or position-sensing devices.


Related Discussions:- Explain about direct-current machines

Requirement specification for the monitor and alarm system, Prepare a User ...

Prepare a User Requirement Specification for the monitor and alarm system. User Requirements Specification should be written in a clear and unambiguous manner to state: • The

Resultant force, State and prove parallelogram law of forces and explain i...

State and prove parallelogram law of forces and explain it''s applications

Calculate minimum number of poles for the induction machine, A wound-rotor ...

A wound-rotor induction machine, driven by a dc motor whose speed can be controlled, is operated as a frequency changer. The three-phase stator winding of the induction machine is

Explain working of encoders, Explain working of Encoders? Encoding is t...

Explain working of Encoders? Encoding is the process of forming an encoded representation of a set of inputs, and it is the converse of the decoding operation. An encoder is a

Digital switching switching in telecommunication, Name the switching scheme...

Name the switching schemes used in a digital exchange

Multiplexer, design a 32:1 multiplexer using two 16:1 multiplexer

design a 32:1 multiplexer using two 16:1 multiplexer

Illustrate transformer coupling, Q. Illustrate Transformer coupling? In...

Q. Illustrate Transformer coupling? In this method the primary winding of the transformer acts as a collector load and the secondary winding transfers the a.c. output signal di

Analog computers, Q. Analog Computers? Although not used as much as the...

Q. Analog Computers? Although not used as much as the digital computer (which nowadays forms the basic tool for numerical analysis and the solution of algebraic as well as diff

Explain extrinsic semiconductor, Explain Extrinsic Semiconductor. Extr...

Explain Extrinsic Semiconductor. Extrinsic Semiconductor: An intrinsic semiconductor is able to conduct some current even at room temperature but as this is not helpful for t

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