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!
Parallel Operation of Interconnected Synchronous Generators
In order to assure continuity of the power supplywithin prescribed limits of frequency and voltage at all the load points scattered over the service area, it becomes necessary in any modern power system to operate several alternators in parallel, interconnected by various transmission lines, in a well-coordinated and optimized manner for the most economical operation. A generator can be paralleled with an infinite bus (or with another generator running at rated voltage and frequency supplying the load) by driving it at synchronous speed corresponding to the system frequency and adjusting its field excitation so that its terminal voltage equals that of the bus. If the frequency of the incoming machine is not exactly equal to that of the system, the phase relation between its voltage and the bus voltagewill vary at a frequency equal to the difference between the frequencies of the machine and the bus voltages. In normal practice, this difference can usually be made quite small, to a fraction of a hertz; in polyphase systems, it is essential that the same phase sequence be maintained on either side of the synchronizing switch. Thus, synchronizing requires the following conditions of the incoming machine:
• Correct phase sequence• Phase voltages in phase with those of the system• Frequency almost exactly equal to that of the system• Machine terminal voltage approximately equal to the system voltage
A synchroscope is used for indicating the appropriate moment for synchronization. After the machine has been synchronized and is part of the system, it can be made to take its share of the active and reactive power by appropriate adjustments of its prime-mover throttle and field rheo stat.
The system frequency and the division of active power among the generators are controlled by means of prime-mover throttles regulated by governors and automatic frequency regulators, whereas the terminal voltage and the reactive volt-ampere division among the generators are controlled by voltage regulators acting on the generator-field circuits and by transformers with automatic tap-changing devices.
Q. What is a clipper circuit? Clipping circuits are linear wave shaping circuits. The main function of 'clipper' is that it clips off a part of input waveform i.e., it cut off
Q. A charge q(t) = 50 + 1.0t C flows into an electric component. Find the current flow.
Q. Illustrate working of Differential Amplifier? Figure shows a weighted differencing amplifier, where "weighted" refers to the fact that the output voltage has the form v o =
For the circuit of Fig 1a: (i) Using Ohm's Law , determine the equivalent resistance across the battery (ii) determine the current through each resistor (iii) the arrang
Define and explain Numerical aperture? Figure shown below shows an incident ray to the fibre, The light bends at two interfaces, one at the air- core interface and the
Describe the effect of following parameters. Abrasive grit size. Amplitude and frequency of vibration.
What are advantages of segmentation ? However because the segment register is 16 bit broad and the memory requires 20 bits for an address the 8086 appends 4 bits segment reg
in industry
what is the literature review about wye delta transformation?? for 3 paragraphs atleast*
Discuss important properties and uses of Ceramics. Ceramics - These are materials made by high temperature firing treatment of natural clay and specific inorganic matters. The
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: +1-415-670-9521
Phone: +1-415-670-9521
Email: [email protected]
All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd