Design, Control and Simulation of PMSG Based Stand-Alone Wind Energy Conversion System

Abstract

In last decade, due to several limitations of conventional sources of energy such as high cost of fossil fuels, contribution towards pollution and environmental damage, scarcity in resources, there is an urge for the utilization of renewable sources of energy. Among several forms of renewable sources of energy, specifically wind energy conversion system is the most cost effective and technologically improvable. In variable speed operation, it is important that the generated power from PMSG should be optimized. Therefore in order to capture as much power as possible from wind during change in wind speed, maximum power point tracking controller is implemented. Among several methods, the most efficient method of MPPT technique is Perturbati on and observation (P&O) which has its own virtues. Here simulation evaluation is done to know the working of MPPT and successfully optimize the generated power during a step change in wind speed.In addition to power optimization, variation in load as well as wind speed during variable speed operation, results drift in system voltage and frequency which in turn leads to generation loss owing to line tripping, power swings and also black outs. Therefore in order to reduce the change in system voltage and frequency to the smallest possible value, a voltage frequency controller is required. Therefore the simulation of WECS with a voltage frequency control using a VSC and BESS is performed. The Voltage frequency controller receives/supplies active/reactive power and hence system voltage and system frequency is maintained almost constant around it`s reference value. For this three phase three wiresystems is considered. The performance of the system is also evaluated for change in load and fault occurrence at line. A PMSG based stand –alone WECS with VF controller is designed, modelled and simulated with MATLAB & SIMULINK.