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

Define capacitor construction, Define Capacitor Construction In its mo...

Define Capacitor Construction In its most elementary state a capacitor having of two metal plates separated by a certain distance d, in among the plates lies a dielectric mate

Calculate maximum reactive power the generator can produce, A 3-phase, wye-...

A 3-phase, wye-connected, 11.8 kV, 100 MVA turbo- generator of 0.8 power factor lagging has a synchronous reactance of 2.0 p.u. on rating. The generator is driven by a steam turbin

Pop instruction, POP Instruction This instruction  copies the contents ...

POP Instruction This instruction  copies the contents  of the top  two locations  of the  stack into the  specified  register pair. The  contents  of stack pointer register are

History of transistor, History of Transistor: The great Physicist Juli...

History of Transistor: The great Physicist Julius Edgar Lilienfeld filed the first patent for a transistor in Canada in the year 1925, explaining a device identical to a Field

Give classification of plastics, Give classification of plastics and al...

Give classification of plastics and also the differences between them. Plastics are materials (containing carbon as common element) that have organic substances of high mol

Emirrer feedback bias, RE should be made large enough to swamp out rB/ B. h...

RE should be made large enough to swamp out rB/ B. how does making RE large saturate the transistor b

Explain the 16-bit registers dptr and sp of 8051, Explain the 16-bit regist...

Explain the 16-bit registers DPTR and SP of 8051. DPTR: DPTR stands for data pointer. DPTR having of a high byte (DPH) and a low byte (DPL). Its function is to hold a 16-b

Electro magnetics and transmission lines, how does the kb come across the s...

how does the kb come across the sheet charge in the amperian sheet?

Calculate the minimum analog output voltage, Q. For a 6-bit weighted-resist...

Q. For a 6-bit weighted-resistor D/A converter, if R is the resistor connected to the MSB, find the other resistor values needed, and calculate the maximum analog output voltage, 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