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

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

What do you mean by external data bus? External Data Bus: A bus which connects a computer to the peripheral devices. The microprocessor-8088 has 16-bit registers, 20-bit add

Enhancement type mosfet, Enhancement type MOSFET In these types of de...

Enhancement type MOSFET In these types of devices operate by comprising a channel enhanced in the semiconductor material in which no channel was constructed, they are termed

find the sending end voltage and current, A 3-phase transmission line is 2...

A 3-phase transmission line is 200km long. The line has a per phase series impedance of 0.25+j0.45 Φ/km and shunt admittance of j7.2ΦS/km. The line delivers 250MVA, at 0.6 lagging

Determine and sketch il for inductance, Q. For the circuit of Figure, deter...

Q. For the circuit of Figure, determine and sketch i L (t) and vC(t) for inductance values of (a)3/4 H, (b) 2/3 H, and (c) 3/17 H. Note that the inductance values are chosen her

Pn junction, the depletion layer in the pn junction is caused by

the depletion layer in the pn junction is caused by

Addressing model , Addressing Model As we have learned  already  that ...

Addressing Model As we have learned  already  that each instruction has two  parts  one is  op code and another  is operand. Op code  specified  the type  of operations to be

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

Explain the construction of synchronous machines, Explain the Construction ...

Explain the Construction of Synchronous Machines? Basically all synchronous machines require a DC excited field winding in order to produce magnetic flux. For majority of machi

Erc and kpi, ERC and KPI The company requires understanding the strate...

ERC and KPI The company requires understanding the strategic and nearing term impact of the Regulator's orders / tariff approval process. Once these dimensions are understood,

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