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

FET, shockely equation?

shockely equation?

What is internal structure of 8086, 8086 is having 2 dissimilar units i.e. ...

8086 is having 2 dissimilar units i.e. BIU(Bus Interface Unit) and EU(Execution Unit), these two units work synchronously.

Cross-subsidy and multi-year tariff - electricity policies, Cross-subsidy:...

Cross-subsidy: The policy gives clarity on determination of cross-subsidy and additional surcharges for open access to consumers and lays down a timeframe for rationalization

Analysis of semiconductor devices, Analysis of Semiconductor Devices T...

Analysis of Semiconductor Devices There are two complementary techniques of studying semiconductor devices: Via numerical simulation of the semiconductor equation

Explain emergency repairs to rail fracture, Q. Explain Emergency Repairs to...

Q. Explain Emergency Repairs to rail fracture? Emergency Repairs - The fractured rails shall be joined by using the arrangements clamps, fish plates. If the gap at fracture doe

Equalizer rings, purpose of equalizer rings in lap winding

purpose of equalizer rings in lap winding

Spectrum analyser, The spectrum analyser plots amplitude against frequency,...

The spectrum analyser plots amplitude against frequency, in other words it shows signals in the frequency domain. The spectrum analyser has the same trigger options as the oscillos

Determine the current and the voltage in the load resistance, Q. Adiodewith...

Q. Adiodewith the i-v characteristic shown in Figure is used in series with a voltage source of 5 V (forward bias) and a load resistance of 1 k. (a) Determine the current and t

Sequential diagram, 1) Draw the state diagram for the state machine describ...

1) Draw the state diagram for the state machine described by Table 7.5 in the text. Note, the table shows the transition to the next state S* from the current state S for the next

Logic Gates, XOR gate BY using NAND gate Only

XOR gate BY using NAND gate Only

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