PERFORMANCE INVESTIGATIONS ON A VARIABLE SPEED CONSTANT FREQUENCY GENERATOR

Abstract

Grid connection of the energy produced from wind is essential if the potential of the wind is to be exploited completely. The major challenge for this is the fact, that speed and direction of the wind vary randomly. The wind turbine driven generators therefore produce power and voltage varying in magnitude and frequency. The variable speed constant frequency (VSCF) scheme discussed in this dissertation employs a power conversion link (AC-DC-AC) to connect the variable frequency output of the wind driven system to the fixed frequency grid. A simulation model necessary to study the performance of the proposed scheme is developed in Matlab/Simulink. A synchronous machine is made to run at different frequencies. This output is rectified using a phase controlled converter and the dc voltage produced is inverted using a line commutated inverter which is connected to the grid. Two control loops one to control the firing angle of converter and the other to control the firing angle of the inverter have also been included.