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.
Explain Magnetostriction. Magnetostriction: If ferromagnetic materials are magnetized a small change of dimensions of the material obtains place. There is a small extension alo
Q. Explain the three-line cable Residential wiring? The three-line cable coming out of the secondaries of the distribution transformer on the utility pole passes through the el
Question: Consider the circuit shown in Figure. There is no initial energy stored in the circuit until time t=0 when the switch is closed. (i) Transform the given circ
Q. For the circuit of Figure: (a) Find an expression for the power absorbed by the load as a function of RL. (b) Plot the power dissipated by the load as a function of the lo
1) Draw the state diagram for the state machine described by Table 7.5 in the text. Note, the table shows the transition to the next state S* from the current state S for the next
Mesh analysis Analysis using KVL to solve for the currents around every closed loop of the network and hence verify the currents through and voltages across every elements of t
Q. Find the number of possible station frequencies in the AM broadcast system in the United States
assignment requirement and specification
Q. The equations for a two-port network are given by V 1 = z 11 I 1 + z 12 I 2 0 = z 21 I 1 + (z 22 + Z L )I 2 V 2 = - I 2 Z L (a) Satisfying the equations, dev
Give the operating modes of 8259a? (a) Automatic Rotation (b) End of Interrupt (EOI) (c) Fully Nested Mode (d) Automatic EOI Mode (e) Specific Rotation (f) Edge
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