A New Induction Motor V/f Control Method Capable of High-Performance Regulation at Low Speeds
Abstract
A novel open-loop speed control method for induction motors that provides high output torque and nearly zero steady-state speed error at any frequency is presented. The control scheme is based on the popular constant volts per hertz (V/f) method using low-cost open-loop current sensors. Only stator current measurements are needed to compensate for both stator resistance drop and slip frequency. The scheme proposed fully compen ....etc

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THEORY:
The regulation of a 3-phase alternator may be predetermined by conducting the Open Circuit (OC) and the Sort Circuit (SC) tests. The methods employed for determination of regulation are EMF or synchronous impedance method, MMF or Ampere Turns method and the ZPF or Potier triangle method. In this experiment, the EMF and MMF methods are used. The OC and SC graphs are plotted from the two tests. The synchronous impedance is found from the OC test. The regulation is then determined at different power factors by ....etc

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presented by:
J.Chaithanya Bharathi
A.L.Harika
P.Divya Sree


ABSTRACT
The performance of any machine can be analyzed with reference to parameters like power factor, total harmonic distortion, voltage regulation, etc. These parameters alter when a machine is subjected to different loads. Depending on the load connected to the system, the voltage and current waveforms are varied. Due to the effect of harmonics, distortion of waveforms from sinusoidal to non sinusoidal is c ....etc

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. Automatic voltage regulation of alternator used in UKAI PP ....etc

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I want ans for this question .plz try to say fast ....etc

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AIM
To conduct OC, SC and ZPF test on the three phase alternator and to predetermine the regulation of 3 phase alternator by EMF method, MMF method, & ZPF method also to verify by vector diagram.
APPARATUS REQUIRED
PRECAUTION
1. The motor field rheostat should be kept in the minimum resistance position.
2. The alternator field potential divider should be in the minimum voltage position.
3. Initially all switches are in open position.
PROCEDURE
A. OC.Test
1. Note down the name ....etc

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HI IAM ramakanth i would like to know why the mmf meathod is optimistic ? and why emf meathod is pesimistic ....etc

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Based on closed form expressions for the power frequency voltages and currents in a typical distribution network, the voltage regulation VR at any time point during the day could be evaluated. It will depend primarily on the network configuration, the daily load curve, the load density and its power factor as well as level of the reactive power compensation.

The computed at a certain time?t? can give a useful indicator for the voltage constancy over the network at that time point. The concept of ?Global Voltage Regulation? is introduced. Th ....etc

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Automatic Voltage regulation technology
Introduction
Excitation system
Automatic voltage regulator
1.Excitation system
What is excitation system ?
Perpose of excitation system.
Type of excitation system
Conventional DC system.
Brushless excitation system.
AC excitation system with noncontrolled diode rectifier.
Alternative excitation system with stationary controlled thyristos rectifier.
Voltage source controlled exciter.
Compound source controlled exciter.
1.Conventional DC system
....etc

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related information of Automatic voltage regulation of alternator ....etc

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