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. Show the boundary of a Word? The boundary of a Word is defined as either 16-bits or the size of the data bus for the processor, and a Double Word is Two Words. so, a Word an
JFET The JFET (junction gate field-effect transistor) is a long channel of semiconductor material, doped to consist of abundance of positive charge carriers (p-type), or
POP Instruction This instruction copies the contents of the top two locations of the stack into the specified register pair. The contents of stack pointer register are
Copy data byte 10H LDAX instruction Example : Copy data byte 10H stored at memory location 3020 H to the accumulator using LDAX instructions. Solution : To use
Register Addressing In this mode the operand are microprocessors registers only i, e the operations is performed within various registers of the microprocessors only.
Q. What is Frequency Translation and Product Modulation? The basic operation needed to build modulators is the multiplication of two signals. Whenever sinusoids are multiplied,
why DC motors use field winding instead of armature winding
example of assignment related to this topic
what is the difference between statically and dynamically induced emf''s
circuit diagrame
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