Download CIRCUIT DIAGRAM Existing System

ANALYSIS AND CONTROL OF CAPACITOREXCITED INDUCTION GENERATORS CONNECTED
TO A MICRO-GRID THROUGH POWER
ELECTRONIC CONVERTERS
ABSTRACT
A system consisting of a capacitor-excited induction generator (CEIG) with associated power electronic
converters has been developed for supplying power to a micro-grid. The power fed to the grid from the CEIG is
controlled using a diode bridge rectifier (DBR) and a pulse width modulated (PWM) inverter, connected between
the generator terminals and the grid. A simple analog based hysteresis current control (HCC) technique has been
employed in which the current control of the PWM inverter alone needs to be carried out by sensing the current and
voltage at the grid terminals.
CIRCUIT DIAGRAM
Existing System
The design and development of renewable energy sources are very much emphasised now-a-days because of the fast
depletion of conventional energy sources and the environmental pollution caused by them. Even though, for such
renewable energy systems, doubly fed induction generators (IG) are being developed, squirrel cage IGs are
continued to be used because of their low cost, simple and robust construction and almost nil maintenance
requirements. These generators are operated either for feeding power directly to the grid or for supplying power to
isolated loads with capacitor excitation. In the case of wind driven systems, the direct grid-connected induction
generators (GCIGs) operate with a small variation in rotor speed from no load to full load, whereas in the case of standalone generators, the rotor speed varies along with the variation in prime mover speed. However, in the case of such
GCIGs also, if the rotor speed is allowed to vary, the machine can be operated with optimum power coefficient and
maximum power (MP) can be extracted and delivered to the grid.
Proposed System
It is shown that the grid power can be represented in the equivalent circuit of CEIG as an equivalent resistance (Re)
only and expression for Re is given in terms of generator phase voltage and the power supplied to the grid. The
sequence of the steps involved in the calculation of the generator parameters for a given power fed to the micro grid
and further predetermination of performance of the entire proposed system has been illustrated in the form of a
flowchart. CEIG are presented for three different patterns of loading, including cube law power extraction for
variable speed wind driven applications. The closeness between the experimental and predicted results validates the
proposed method of analysis and also the successful working of the simple analog hysteresis control technique, for
different renewable energy applications.
TOOLS AND SOFTWARE USED:
 MP LAB
 ORCAD/PSPICE
 MATLAB/SIMULINK
OUTPUT:
 HARDWARE
 SIMULATION