Improvement of voltage and current quality in wind turbine generator using parallel compensation

Abstract

In wind generation at low wind speed sites, vertical-axis wind turbines (VAWT) are preferred and the most commonly used type of generator for this micro wind system is the Permanent Magnet Synchronous Generator (PMSG) known for its high efficiency and low cost. As for the power converter, previous researches have shown that PMSG connected to active (PWM) rectifier provides better power quality in terms of power factor, stable dc link voltage and pure ac current compared the conventional diode rectifier used. The drawback of PWM rectifier is that it is very costly and more complex to be constructed. This study evaluated and analysed the power condition performance when a capacitor bank is placed between the PMSG and diode rectifier as an alternative to the PWM rectifier. This study also focused on investigating the optimum size of the shunt capacitor that provides a better voltage and current signal and compare the performance of proposed system to a conventional PMSG-connected to diode rectifier.