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.
Ask question #Discuss the role of load factor on the cost of electrical energy 100 words accepted#
Q. Illustrate working of Application Layer? As the highest layer in OSI reference model, application layer provides services to users of OSI environment. Layer
assume that the top of the stack in the program is pointed by the register sp.
Q. A source of impedance ¯ Z S = R S = 100 has an open-circuit voltage v S (t) = 12.5 cos ωot and drives a 75- transmission line terminated with a 75- load. Find the current
Torque-Speed Characteristics of 3-Phase Induction Motors Because the torque-slip characteristic is one of themost important aspects of the inductionmotor, we will now develop a
Explain and drive the expression for fixed bias and potential divider.
Magnetic materials
Saturation or active mode While V GS > V th and V DS > (V GS - V th ) The switch is turned on, and a channel has been made that allows current to flow
Hysteresis loss least depends on (A) Frequency. (B) Magnetic field intensity. (C) Volume of the material. (D)Grain orientation of material.
What are the Advantages of using robots - They are able to work non-stop; they don't need a break - They are capable of working in conditions hazardous to humans - Ess
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