Explain the synchronous machines, Electrical Engineering

Assignment Help:

Explain the Synchronous Machines?

A synchronous machine, unlike an induction (or asynchronous) machine, only develops torque at a fixed, so called, synchronous speed - ns which is related to the supply frequency f and the number of pole-pairs p as follows:

ns = 60 . f / p

The main application of a synchronous machine is as a generating device for the bulk conversion of mechanical energy (from a gas, steam or water turbine or a diesel engine) to electrical energy. It is therefore found in all types of power generating stations and also standby generating plants. In the case of a steam plant, the machine is often referred to as a turbo-generator, turbine generator or turbo-alternator. Electrical machines are in general reversible in nature meaning that they are capable of operating both as a motor and as a generator. In this sense, the synchronous machine is no exception. A good example of this are pumped-storage hydro-electric schemes such as the one at Dinorwig in North Wales comprising 6 x 315-MW synchronous machines which can be operated as generators or motors. Synchronous motors are more expensive to install than induction motors and are only found in relatively small numbers in industry where there is a requirement both for a constant-speed drive and the ability of reactive power control.

If inverter-fed they can be used in high-speed variable speed drives for traction applications. Small single-phase synchronous motors have been widely used to provide a timing mechanism for processes such as washing machine cycles. A permanent magnet synchronous machine, usually termed as a DC brushless machine, serves as a basis for numerous high performance servo applications for machine tools and industrial robots. The objective of this module is to look at synchronous machines as a central part of a power generation system. In this sense, the following sections will discuss only the fundamental theory of classical synchronous generators and not the machine operating characteristics in motoring mode.


Related Discussions:- Explain the synchronous machines

Find the rotor copper loss, A three-phase, 50-hp, 440-V, 60-Hz, four-pole, ...

A three-phase, 50-hp, 440-V, 60-Hz, four-pole, wound-rotor inductionmotor operates at a slip of 0.03 at full load,with its slip rings short-circuited. The motor is capable of devel

Condition return, Condition Return Similar to conditional jump and cal...

Condition Return Similar to conditional jump and call  instructions there are conditional return  instructions  also  based on various  flags.

What do you mean by diversifiability of total risk, Q. What do you mean by ...

Q. What do you mean by diversifiability of total risk? Traditional finance theory assets that the rate of return on risk assets depends on the size of business risk, financial

Fet operation, FET operation: Figure: I-V characteristics and o...

FET operation: Figure: I-V characteristics and output plot of a JFET n-channel transistor. The FET manages the flow of electrons (or electron holes) from the sourc

Pneumatics, Design and draw a circuit using the cascade system to operate t...

Design and draw a circuit using the cascade system to operate two cylinders (A and B) which, on the operation of a start valve, produces the sequence A – B + B – A+. The cylinders

Illustrate about the digital televisions, Illustrate about the Digital tele...

Illustrate about the Digital televisions Microprocessor would be used to control the below features, for instance: - Automatically tuning into television stations - allow

Spectral analysis and signal bandwidth, Q. Show Spectral Analysis and Signa...

Q. Show Spectral Analysis and Signal Bandwidth? Spectral analysis is based on the fact that a sinusoidal waveform is completely characterized by three quantities: amplitude, ph

Explain the working of direct memory access controller, Explain the various...

Explain the various modes in which DMAC works. Working of Direct memory access controller: The modes of operation has demand mode, block mode, single mode and cascade mode.

What is button, A button does some command in a program when it is clicked....

A button does some command in a program when it is clicked. Buttons generally have a 3-dimensional look, although you may have to move the mouse over the button for it to look 3D.

Tampering of, Damage of revolving metallic disc due to tampering

Damage of revolving metallic disc due to tampering

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