Already have an account? Get multiple benefits of using own account!
Login in your account..!
Remember me
Don't have an account? Create your account in less than a minutes,
Forgot password? how can I recover my password now!
Enter right registered email to receive password!
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.
Q. Illustrate the principle of alignment? Pieces of highly permeablematerial, such as iron, situated in ambientmediumof lowpermeability, such as air, in which a magnetic field
Explain Microprocessor development system. Microprocessor development system: Computer systems consist of undergone many changes lately. Machines which once filled large area
Explain the Alphanumeric Coding - bcd to decimal conversion? For the inherently binary world of computer, it is necessary to put all symbols, letters, numbers, and so on into bin
The free electron theory of metals was first proposed by Drude and later improved by Lorentz. The main postulates of this theory are 1. All metal contain, adequate number
Describe in brief the Formation of energy bands in solids and hence explain how it helps to classify the solid in to conductors and insulators. Energy Bands in Solids Acco
Why do potential barriers breaks when a breakdown voltage is application to semiconductor
Explain the energy bands in solids. There are as several energy bands in a solid as there are energy levels in the parent atoms. Many electrical properties of significance
purpose of sheilding
Q. Illustrate BCD-to-decimal decoding with a 4-to- 16 decoder, and draw the corresponding truth table.
Q. Explain Fourier Series? The phasor method of circuit analysis can be extended (by using the principle of superposition) to find the response in linear systems due to nonsinu
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!
whatsapp: +91-977-207-8620
Phone: +91-977-207-8620
Email: [email protected]
All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd