The paper presents the advanced control system of the wind energy conversion with a variable speed wind turbine. The considered system consists of a wind turbine with the permanent magnet synchronous generator (PMSG), machine side converter (MSC), grid side converter (GSC) and control circuits. The mathematical models of a wind turbine system, the PMSG generator and converters have been described. The control algorithms of the converter systems based on the methods of vector control have been applied. In the advanced control system of the machine side converter the optimal MPPT control method has been used. Additionally the pitch control scheme is included in order to achieve the limitation of maximum power and to prevent mechanical damage of the wind turbine. In the control system of the grid side converter the control of active and reactive power has been applied with the application of Voltage Oriented Control (VOC). The performance of the considered wind energy system has been studied by digital simulation. The results of simulation studies confirmed the good effectiveness of the considered wind turbine system and very good performance of the proposed methods of vector control and control systems.

Wind and solar radiation are intermittent with stochastic fluctuations, which can influence the stability of operation of the hybrid system in the grid integrated mode of operation. In this research work, a smoothing control method for mitigating output power variations for a grid integrated wind/PV hybrid system using a battery and electric double layer capacitor (EDLC) is investigated. The power fluctuations of the hybrid system are absorbed by a battery and EDLC during wide variations in power generated from the solar and wind system, subsequently, the power supplied to the grid is smoothened. This makes higher penetration and incorporation of renewable energy resources to the utility system possible. The control strategy of the inverter is realized to inject the power to the utility system with the unity power factor and a constant DC bus voltage. Both photovoltaic (PV) and wind systems are controlled for extracting maximum output power. In order to observe the performance of the hybrid system under practical situations in smoothing the output power fluctuations, one-day practical site wind velocity and irradiation data are considered. The dynamic modeling and effectiveness of this control method