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.
What do you mean by Bezier curve? Shown B0 (1,1), B1 (2,3), B2 (4,3), B3 (3,1) the vertices of Bezier polygon, calculate seven points on Bezier curve. Write in brief the differe
For Sign Flag JP ( jump on plus ) Jump on minus ) Instructions JP transfer the execution of the program to the specified memory address if sign flag is set (S=
N-type semiconductor is an example of (A) Extrinsic semiconductor. (B) Intrinsic semiconductor. (C) Super conductor. (D) Insulators.
State by inspection (i.e. without performing any formal analysis) all you can about each of the periodic waveforms shown in FIGURE 1 in terms of their Fourier series when analysed
describe the compensation technique for both Vbe and Icbo
Addition of trivalent impurity to a semiconductor creates many (A) Holes. (B) Free electrons. (C) Valance electrons. (D) Bound electrons. Ans: Addition o
Q. Explain about Dial Pulses? Dial pulsing (sometimes known as rotary dial pulsing) is the method basically used to transfer digits from a telephone set to the local switch. Pu
Energy Meter 1. The energy meter is the cash register of the utility. Energy meters form a vital instrument of revenue realization for the Supply Utilities. Based on the meter
Emitter bias: Figure: Emitter bias While a split supply (dual power supply) is accessible, this biasing circuit is the very much effective, and gives zero bias vo
The worldwide automotive industry is currently witnessing rapid innovative developments day by day. The developments encompass every aspect of the automobile such as materials, man
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