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

Give the operating modes of 8259a, Give the operating modes of 8259a? (...

Give the operating modes of 8259a? (a) Automatic Rotation (b) End of Interrupt (EOI) (c) Fully Nested Mode  (d) Automatic EOI Mode (e) Specific Rotation (f) Edge

Illustrate the experts model of GPS system, Illustrate the experts model of...

Illustrate the experts model of GPS System A fundamental expert system is made up of the below elements: Setting up an Expert System -  Information is collected

Three phase power measurement, what is the relationship between the inducta...

what is the relationship between the inductance, capacitance and resistance in the 2-wattmeter experiment?

Gunawan, conclusion about electrical engireng??

conclusion about electrical engireng??

Effect of feedback on sensitivity to parameter changes, Q. Effect of feedba...

Q. Effect of feedback on sensitivity to parameter changes? A good control system, in general, should be rather insensitive to parameter variations, while it is still able to fo

Explain the properties of low resistivity materials, Explain the properties...

Explain the properties of low resistivity materials. Low resistivity materials: The conducting materials containing resistivity from 10 -8 to 10 -6 ohm-m come under this cl

Define sampling at a very high frequency, Define Sampling at a Very High Fr...

Define Sampling at a Very High Frequency? By sampling at a very high frequency compared with the signal frequency, we can ensure that we do not miss important information. Anot

What do you mean by internal data bus, What do you mean by internal data bu...

What do you mean by internal data bus? Internal Data Bus: A bus which operates only in the internal circuitry of the CPU, communicating between the internal caches of memory

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

Explain the electrical contact materials with examples, Explain the electri...

Explain the electrical contact materials with examples. Electrical contact materials: A number of elements in their pure form as copper, nickel, palladium, molybdenum, platin

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